247 results on '"Robertson LJ"'
Search Results
2. Glutathione S-transferase expression in benign and malignant ovarian tumours
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Green, JA, primary, Robertson, LJ, additional, and Clark, AH, additional
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- 1993
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3. Graduates' reflections on their preparation for practice.
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Robertson LJ and Griffiths S
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OCCUPATIONAL therapy ,PHYSICAL therapy ,MEDICAL rehabilitation ,MEDICAL care ,PUBLIC health ,PHYSICAL therapists ,THERAPEUTICS ,OCCUPATIONAL therapists - Abstract
New graduates are the life blood of the occupational therapy profession. It is important that they are equipped to practise in the current health care environment and are confident about their professional contribution. This New Zealand study explored new graduates' perceptions of how well they had been prepared for practice, using three focus groups of graduates from one occupational therapy programme. The findings confirmed that the biggest issues for new graduates were searching for role clarity, inadequate supervision, an insufficient grasp of skills and uncertainty in team responsibility, underpinned by a lack of confidence. Conversely, they felt confident about their ability to research and find information in response to gaps in their knowledge. This study demonstrates that learning how to 'be' an occupational therapist is as important as receiving formal supervision, and suggests that learning how to contextualise and reconstruct knowledge is essential in preparation for graduation. The stressful situations experienced in the first months of practice could be minimised through opportunities to learn how to repackage knowledge, observe role models and have supervision that provides confirmation of plans and bridges the theory-practice divide. [ABSTRACT FROM AUTHOR]
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- 2009
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4. Hard complexities -- soft complexities: an exploration of philosophical positions related to evidence in occupational therapy.
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Blair SEE and Robertson LJ
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- 2005
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5. Giardia duodenalis in sympatric wild reindeer and domestic sheep in Norway.
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Utaaker KS, Kifleyohannes T, Ytrehus B, Robertsen PA, Strand O, and Robertson LJ
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Wild and semi-domesticated reindeer graze freely on natural pastures in Norway, often sharing these with domestic sheep and other domestic and wild ruminants. In this study, faecal samples from wild reindeer and domestic sheep were collected from two areas in southern Norway and analysed to assess the occurrence and assemblage of Giardia duodenalis. Among 162 wild reindeer samples, 25 (15%) were positive for Giardia , showing high infection intensities, with most of the samples belonging to sub-assemblage AI, which has zoonotic potential. Interestingly, this study did not detect subassemblage AIII, known to be found in wild ruminants. Among 45 sheep samples, 13 (29%) were Giardia- positive, with most belonging to assemblage E. The finding of predominantly assemblage AI in the reindeer was surprising, particularly given the large proportion of sheep shedding assemblage E Giardia cysts. As the number of sheep on these natural pastures far outnumbers the wild reindeer, it is intriguing that they do not seem to share Giardia assemblages., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)
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- 2024
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6. First case of autochthonous Angiostrongylus vasorum infection in a Norwegian dog.
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Robbestad J, Jiménez-Meléndez A, Robertson LJ, Vatne LI, Hauback MN, and Nerhagen S
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- Animals, Dogs, Norway, Male, Female, Strongylida Infections veterinary, Strongylida Infections diagnosis, Strongylida Infections drug therapy, Strongylida Infections parasitology, Angiostrongylus isolation & purification, Dog Diseases parasitology, Dog Diseases diagnosis, Dog Diseases drug therapy
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A fifteen-month-old Pembroke Welsh corgi with respiratory distress, exercise intolerance, and moderate regenerative anemia was referred to The Norwegian University of Life Sciences, Small Animal Hospital.Hematology revealed moderate regenerative anemia without evidence of hemolysis. Thoracic radiographs showed a generalized mixed interstitial to alveolar lung pattern and enlarged pulmonary arteries. Changes suggestive of moderate pulmonary hypertension were noted on echocardiography. Baermann fecal diagnostic flotation identified large numbers of Angiostrongylus vasorum larvae, and the AngioDetect serological antigen test was positive. The dog was treated with a two-week course with fenbendazole (51 mg/kg q24h po) and topical imidacloprid/moxidectin (250 mg/62.5 mg) and a one-week course with sildenafil (0.45 mg/kg q12h po). Complete clinical, clinicopathological and echocardiographic resolution was observed after only four weeks. Rapid improvement of echocardiographic abnormalities in cases with suspected pulmonary hypertension is not usually reported in cases with angiostrongylosis.Infection with A. vasorum should be considered in dogs with respiratory signs and bleeding tendencies, even in countries with no endemic history or reported cases., (© 2024. The Author(s).)
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- 2024
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7. Cryptosporidium species and subtypes in Norway: predominance of C. parvum and emergence of C. mortiferum .
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Tipu JH, Sivertsen A, Afset JE, Sandven L, Brekke H, Lund HM, Elburg LS, Gaustad P, Lier T, Tverelv LR, Johansen ØH, Robertson LJ, and Hanevik K
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- Humans, Norway epidemiology, Child, Child, Preschool, Adult, Animals, Female, Male, Adolescent, Young Adult, Infant, Middle Aged, Phylogeny, Disease Outbreaks, Aged, Cryptosporidium parvum genetics, Cryptosporidium parvum classification, Cryptosporidium parvum isolation & purification, DNA, Protozoan genetics, Cryptosporidiosis epidemiology, Cryptosporidiosis parasitology, Cryptosporidium genetics, Cryptosporidium classification, Cryptosporidium isolation & purification, Feces parasitology, Genotype
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PCR-based diagnostics has revealed the previously largely unknown Cryptosporidium transmission and infections in high-income countries. This study aimed to determine domestic and imported subtypes of Cryptosporidium species in Norway, evaluate their demographic distribution, and identify potential small outbreaks. Cryptosporidium -positive human faecal samples were obtained from six medical microbiology laboratories between February 2022 and January 2024, together with 22 Cryptosporidium -positive animal samples. Species and subtypes were identified by sequencing PCR products from gp60 and SSU rRNA genes. Most cryptosporidiosis cases occurred during late summer/early autumn, primarily in children and young adults. Of 550 human samples, 359 were successfully characterized molecularly (65%), revealing infection with 10 different Cryptosporidium species. C. parvum occurred in 245 (68%) human isolates with IIa and IId being major allele families, with distinct regional distribution patterns of common subtypes. A kindergarten outbreak with 5 cases was due to C. parvum IIaA14G1R1. C. mortiferum was identified in 33 (9.2%) human cases of which 24 were known to be of domestic origin, making it the second most common species in human autochthonous cases in Norway. All C. mortiferum isolates were of the same genotype; XIVaA20G2T1, including 13 cases from a suspected small outbreak in Trøndelag. C. hominis occurred in 68 typed cases (19%), but mostly in infections acquired abroad, with allele families Ib and If occurring most often. In conclusion, this study of recent Cryptosporidium spp. and subtypes in Norway, highlights the predominance of C. parvum and the emergence of C. mortiferum among autochthonous cases.
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- 2024
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8. Estimation of diagnostic sensitivity and specificity of abattoir registrations and bulk tank milk ELISA as herd-level tests for Fasciola hepatica using Bayesian latent class modelling.
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Opsal T, Denwood MJ, Hektoen L, Robertson LJ, and Toftaker I
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- Animals, Cattle, Norway epidemiology, Female, Prevalence, Antibodies, Helminth analysis, Fascioliasis veterinary, Fascioliasis diagnosis, Abattoirs, Enzyme-Linked Immunosorbent Assay veterinary, Enzyme-Linked Immunosorbent Assay methods, Fasciola hepatica isolation & purification, Fasciola hepatica immunology, Bayes Theorem, Cattle Diseases diagnosis, Cattle Diseases parasitology, Sensitivity and Specificity, Milk parasitology, Milk chemistry, Latent Class Analysis
- Abstract
The common liver fluke, Fasciola hepatica, is a trematode parasite found worldwide, typically with a focal distribution due to its requirement for suitable climatic and environmental conditions to complete its lifecycle. Bovine fasciolosis causes suboptimal production and economic losses, including liver condemnation at slaughter. The lack of reliable diagnostic methods is a disadvantage to the increasing demand for surveillance and control. The aim of this study was to evaluate the diagnostic accuracy of bulk tank milk (BTM) antibody testing and aggregated abattoir registrations (AAR) of liver fluke as herd-level tests for F. hepatica infection using Bayesian latent class models. Data from the abattoirs in 2019-2021 and BTM, sampled in the winter of 2020/2021, were collected from 437 herds on the southwest coast of Norway. The BTM samples were analysed with the SVANOVIR® F. hepatica-Ab ELISA test, with results given as an optical density ratio (ODR), and later dichotomized using the recommended cut-off value from the test manufacturer (ODR ≥0.3). Based on the BTM ELISA test, 47.8% of the herds tested positive. The AAR test was defined as the herd-level proportion of female slaughtered animals registered with liver fluke infection during the study period. For this test, three cut-offs were used (a proportion of 0.05, 0.1 and 0.2). The herds were split into two subpopulations ("Coastal" and "Inland"), which were expected to differ in true prevalence of F. hepatica infection based on climate-related and geographical factors. The diagnostic accuracies of both tests were estimated using Bayesian latent class models with minimally informative priors. Post-hoc analysis revealed that the maximum sum of sensitivity (Se) and specificity (Sp) of the tests was achieved with a herd-level proportion of ≥0.1 registered with liver fluke as the AAR test. Using this cut-off, the median estimate for the diagnostic accuracy of the BTM ELISA was 90.4% (84.0-96.2 95% Posterior Credible Interval (PCI)) for Se and 95.3% (90.6-100% PCI) for Sp, while the median estimate of Se for AAR was 87.5% (81.4-93.1% PCI) and the median estimate of Sp for AAR was 91.0% (85.2-96.5% PCI). The cut-off evaluation of the SVANOVIR® F. hepatica-Ab ELISA test for BTM confirmed the manufacturer's recommended cut-off of ODR ≥0.3 to denote positive and negative herds. This study suggests that AAR and BTM ELISA test can be used as herd-level tools to monitor liver fluke infection, so that appropriate interventions against infection can be implemented as necessary., Competing Interests: Declaration of competing interest The authors declare that they have no competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)
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- 2024
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9. Occurrence and factors associated with Cryptosporidium infection in livestock in three districts of Zambia.
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Mwaba F, Robertson LJ, Tembo R, Zulu M, Ngalamika O, Phiri AM, and Siwila J
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- Animals, Zambia epidemiology, Sheep, Risk Factors, Male, Cattle, Female, Prevalence, Seasons, Livestock parasitology, Cryptosporidiosis epidemiology, Cryptosporidiosis parasitology, Goats, Goat Diseases epidemiology, Goat Diseases parasitology, Cryptosporidium isolation & purification, Sheep Diseases epidemiology, Sheep Diseases parasitology, Feces parasitology, Cattle Diseases epidemiology, Cattle Diseases parasitology
- Abstract
Cryptosporidium is one of the most important enteric diarrhoeal parasites that infect humans and animals worldwide. The current study investigated the occurrence and risk factors associated with Cryptosporidium infection in ruminants aged ≤6 months in Monze, Mumbwa, and Lusaka districts of Zambia. Faecal samples were collected from 328 calves, 190 lambs, and 245 goat kids and analysed for Cryptosporidium oocysts using modified Ziehl Neelsen staining. A closed structured questionnaire was used to obtain epidemiological characteristics and potential risk factors for Cryptosporidium infection. The overall occurrence of Cryptosporidium was 7.9% (60/763), while that in calves, lambs and goat kids was 14.5% (47/328), 5.3% (10/190), and 1.2% (3/245) respectively. Watery/pasty stool and sampling during the rainy season were independently associated with increased risk of infection. In calves, the odds of infection increased during the rainy season, while daily kraal cleaning reduced the infection risk. Lambs showed increased odds of infection with pasty/watery stool and male sex, whereas the wearing of protective clothing by handlers significantly reduced the risk. There were district variations in infection occurrence with Mumbwa district having higher prevalence. The findings of this study show that livestock in Zambia continue to be frequently infected with Cryptosporidium. Protective measures and appropriate farm cleanliness should be implemented in control of this infection. Regional and host-species-specific variations emphasize the need for targeted interventions. These findings, therefore, contribute to effective strategies for Cryptosporidium control, promoting good livestock health and management., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)
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- 2024
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10. Investigating the potential of X chromosome shredding for mouse genetic biocontrol.
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Bunting MD, Godahewa GI, McPherson NO, Robertson LJ, Gierus L, Piltz SG, Edwards O, Tizard M, and Thomas PQ
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- Animals, Male, Mice, Female, RNA, Guide, CRISPR-Cas Systems genetics, Spermatozoa metabolism, Mice, Transgenic, Meiosis genetics, CRISPR-Cas Systems, Spermatogenesis genetics, X Chromosome genetics
- Abstract
CRISPR-Cas9 technology has facilitated development of strategies that can potentially provide more humane and effective methods to control invasive vertebrate species, such as mice. One promising strategy is X chromosome shredding which aims to bias offspring towards males, resulting in a gradual and unsustainable decline of females. This method has been explored in insects with encouraging results. Here, we investigated this strategy in Mus musculus by targeting repeat DNA sequences on the X chromosome with the aim of inducing sufficient DNA damage to specifically eliminate X chromosome-bearing sperm during gametogenesis. We tested three different guide RNAs (gRNAs) targeting different repeats on the X chromosome, together with three male germline-specific promoters for inducing Cas9 expression at different stages of spermatogenesis. A modest bias towards mature Y-bearing sperm was detected in some transgenic males, although this did not translate into significant male-biasing of offspring. Instead, cleavage of the X chromosome during meiosis typically resulted in a spermatogenic block, manifest as small testes volume, empty tubules, low sperm concentration, and sub/infertility. Our study highlights the importance of controlling the timing of CRISPR-Cas9 activity during mammalian spermatogenesis and the sensitivity of spermatocytes to X chromosome disruption., (© 2024. The Author(s).)
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- 2024
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11. Occurrence of gastrointestinal nematodes in lambs in Norway, as assessed by copromicroscopy and droplet digital polymerase chain reaction.
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Gravdal M, Woolsey ID, Robertson LJ, Höglund J, Chartier C, and Stuen S
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- Animals, Norway epidemiology, Sheep, Prevalence, Nematoda isolation & purification, Microscopy veterinary, Sheep Diseases epidemiology, Sheep Diseases parasitology, Polymerase Chain Reaction veterinary, Feces parasitology, Nematode Infections veterinary, Nematode Infections epidemiology, Nematode Infections parasitology
- Abstract
Background: Gastrointestinal nematodes (GINs) have a major impact on sheep production, health, and welfare worldwide. Norway is no exception, but there are only a few studies on the prevalence of GINs in Norwegian sheep. The aim of this study was to investigate the current occurrence of the most important nematodes in sheep flocks in Norway. Faecal samples were collected from flocks in 2021/2022, mainly from three geographical regions in Norway, i.e., northern, eastern, and western. In each of 134 flocks included, individual samples from 10 lambs (autumn) were pooled. Third stage larvae (L3) were cultivated and harvested (Baermann method) from the pooled samples. The DNA was then extracted and further analysed using droplet digital PCR (ddPCR). This enables assessment of the proportions of the three most important nematode species/genera, i.e., H. contortus, T. circumcincta, and Trichostrongylus. The fractional abundance/relative proportion of each species/genus was assessed by performing duplex assays with universal strongyle and species/genus-specific primers and probe sets. In addition, the occurrence of Nematodirus eggs was assessed by standard faecal egg counts (i.e., McMaster method)., Results: Of the 134 flocks sampled, 24 were from the northern region, 31 from eastern, and 71 from western Norway. In addition, some flocks from central (n = 7), and southern (n = 1) Norway were included. Among the sampled flocks, T. circumcincta occurred most commonly (94%), followed by H. contortus (60%) and Trichostrongylus (55%), and Nematodirus (51%). In general, mixed infections were observed, with 38% and 18% of flocks infected with three or all four genera, respectively., Conclusions: The results of this study indicate that GINs are widespread in Norway. Teladorsagia circumcincta seems to be present in most flocks based on this screening. Moreover, the results show that Nematodirus spp. infect lambs throughout the country, predominantly N. battus, and indicate that this nematode has become more abundant, which could lead to an increase in nematodirosis., (© 2024. The Author(s).)
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- 2024
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12. Current and potential future impacts of food- and water-borne parasites in a changing world: A Norwegian perspective.
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Robertson LJ, Woolsey ID, and Jiménez-Meléndez A
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In 2021, the Norwegian Scientific Committee for Food and Environment published a multi-criteria risk ranking of 20 potentially food-borne pathogens in Norway. The pathogens ranked included five parasite taxa (3 species, one genus, one family): Toxoplasma gondii , Echinococcus multilocularis , Giardia duodenalis , Cryptosporidium spp., and Anisakidae. Two of these, T. gondii and E. multilocularis , scored very highly (1st and 3rd place, respectively), Cryptosporidium was about midway (9th place), and G. duodenalis and Anisakidae ranked relatively low (15th and 20th place, respectively). Parasites were found, on average, more likely to present an increasing food-borne disease burden in the future than the other pathogens. Here, we review the current impact of these five potentially food-borne parasites in Norway, and factors of potential importance in increasing their future food-borne disease burden. Climate change may affect the contamination of water and fresh produce with transmission stages of the first four parasites, potentially leading to increased infection risk. Alterations in host distribution (potentially due to climate change, but also other factors) may affect the occurrence and distribution of Toxoplasma , Echinococcus , and Anisakidae, and these, coupled with changes in food consumption patterns, could also affect infection likelihood. Transmission of food-borne pathogens is complex, and the relative importance of different pathogens is affected by many factors and will not remain static. Further investigation in, for example, ten-years' time, could provide a different picture of the relative importance of different pathogens. Nevertheless, there is clearly the potential for parasites to exert a greater risk to public health in Norway than currently occurs., Competing Interests: Ian D. Woolsey and Alejandro Jiménez-Meléndez declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Lucy J. Robertson declares that she is a member of the Panel for Biological Hazards of the Norwegian Scientific Committee for Food and Environment (VKM) and participated in the risk ranking that provided the initial inspiration for this article., (© 2024 The Authors.)
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- 2024
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13. Towards an actionable One Health approach.
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Zhang XX, Lederman Z, Han LF, Schurer JM, Xiao LH, Zhang ZB, Chen QL, Pfeiffer D, Ward MP, Sripa B, Gabriël S, Dhama K, Acharya KP, Robertson LJ, Deem SL, Aenishaenslin C, Dantas-Torres F, Otranto D, Grace D, Wang Y, Li P, Fu C, Poeta P, Md Tanvir Rahman, Kassegne K, Zhu YZ, Yin K, Liu J, Wang ZJ, Guo XK, Gong WF, Schwartländer B, Ren MH, and Zhou XN
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- Animals, Asia, Capacity Building, Policy, Zoonoses prevention & control, One Health
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Background: Despite the increasing focus on strengthening One Health capacity building on global level, challenges remain in devising and implementing real-world interventions particularly in the Asia-Pacific region. Recognizing these gaps, the One Health Action Commission (OHAC) was established as an academic community for One Health action with an emphasis on research agenda setting to identify actions for highest impact., Main Text: This viewpoint describes the agenda of, and motivation for, the recently formed OHAC. Recognizing the urgent need for evidence to support the formulation of necessary action plans, OHAC advocates the adoption of both bottom-up and top-down approaches to identify the current gaps in combating zoonoses, antimicrobial resistance, addressing food safety, and to enhance capacity building for context-sensitive One Health implementation., Conclusions: By promoting broader engagement and connection of multidisciplinary stakeholders, OHAC envisions a collaborative global platform for the generation of innovative One Health knowledge, distilled practical experience and actionable policy advice, guided by strong ethical principles of One Health., (© 2024. The Author(s).)
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- 2024
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14. Mental health services in Gauteng, South Africa: A proxy evaluation using pharmaceutical data.
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Robertson LJ and Bouwer JC
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Background: South African legislation advocates for equitable access to mental healthcare services integrated into general healthcare settings. Mental, neurological, and substance use (MNS) disorders are often comorbid. Pharmacoepidemiology provides indirect evidence of service provision for conditions amenable to medicine treatment., Aim: The study aims to evaluate medicine procurement for MNS disorders at different service levels in the health system., Setting: The Public health sector, Gauteng province formed the setting for the study., Method: A secondary analysis of the Gauteng pharmaceutical database was conducted using Anatomic Therapeutic Chemical (ATC) and defined daily dose (DDD) methodology. Anatomic Therapeutic Chemical classes of medicines for MNS disorders were included. Defined daily doses and costs were calculated per 1000 population served by each facility and service level. Statistical comparisons were made using chi-square testing., Results: General healthcare settings accounted for 90% (R118 638 248) and specialised hospitals for 10% (R13 685 032) of expenditure on medicines for MNS disorders, procuring 94% ( n = 49 442 474) and 6% ( n = 3 311 528) of DDDs, respectively. Although district clinics procured 60% of DDDs, they procured the least per 1000 population served, whereas district hospitals procured the most. For almost all ATC classes, procurement differed significantly between municipalities at every service level and between specialised hospitals., Conclusion: In Gauteng province, most medicines for MNS disorders are procured by general healthcare services, but access to care may not be equitable. While population coverage at district clinics appears low, district hospitals may experience the greatest care burden. Research regarding quality of care at each service level is recommended., Contribution: This study provides insight into service provision for MNS disorders., Competing Interests: The authors declare that they have no financial or personal relationships that may have inappropriately influenced them in writing this article., (© 2024. The Authors.)
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- 2024
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15. The importance of estimating the burden of disease from foodborne transmission of Trypanosoma cruzi.
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Robertson LJ, Havelaar AH, Keddy KH, Devleesschauwer B, Sripa B, and Torgerson PR
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- Animals, Cost of Illness, Trypanosoma cruzi, Chagas Disease epidemiology, Triatoma, Foodborne Diseases epidemiology
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Chagas disease (ChD), caused by infection with the flagellated protozoan, Trypanosoma cruzi, has a complicated transmission cycle with many infection routes. These include vector-borne (via the triatomine (reduviid bug) vector defecating into a skin abrasion, usually following a blood meal), transplacental transmission, blood transfusion, organ transplant, laboratory accident, and foodborne transmission. Foodborne transmission may occur due to ingestion of meat or blood from infected animals or from ingestion of other foods (often fruit juice) contaminated by infected vectors or secretions from reservoir hosts. Despite the high disease burden associated with ChD, it was omitted from the original World Health Organization estimates of foodborne disease burden that were published in 2015. As these estimates are currently being updated, this review presents arguments for including ChD in new estimates of the global burden of foodborne disease. Preliminary calculations suggest a burden of at least 137,000 Disability Adjusted Life Years, but this does not take into account the greater symptom severity associated with foodborne transmission. Thus, we also provide information regarding the greater health burden in endemic areas associated with foodborne infection compared with vector-borne infection, with higher mortality and more severe symptoms. We therefore suggest that it is insufficient to use source attribution alone to determine the foodborne proportion of current burden estimates, as this may underestimate the higher disability and mortality associated with the foodborne infection route., Competing Interests: I have read the journal’s policy and the authors of this manuscript have the following competing interests: LJR, KHK, BD, BS, PRT are members of the Parasitic Diseases Task Force of (The Foodborne Disease Burden Epidemiology Reference Group (FERG)) currently instituted by WHO. AHH is involved in the FERG endeavour as a consultant for WHO., (Copyright: © 2024 Robertson et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
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- 2024
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16. Preliminary investigations of parasite contamination of water sources in Armenia.
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Shcherbakov OV, Aghayan SA, Gevorgyan HS, Abgaryan TA, Gevorgyan RH, Jiménez-Meléndez A, and Robertson LJ
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The intestinal protozoan parasites, Cryptosporidium and Giardia , are known to have a global distribution, infecting and causing disease in a range of hosts, including people, livestock, pets, and wildlife. However, data from some regions is very sparse. In Armenia, in the Caucasus region of West Asia, only scanty data are available, with just a few surveys on Cryptosporidium infections in livestock, and no available data on human infections or environmental contamination. As part of implementation of water analysis methods for these parasites in Armenia, 24 raw water samples and two sediment samples were analysed for these parasites using a range of approaches, including modified Ziehl-Neelsen, Lugol stain, immunofluorescent antibody test (IFAT), qPCR and, on sediment samples, immunomagnetic separation and IFAT. Results suggest substantial contamination of raw water sources and indicate the need for further targeted studies using appropriate methods and collecting data on host infections in catchment areas., Competing Interests: Lucy J. Robertson reports a relationship with European Federation of Parasitologists that includes: board membership. Lucy J Robertson reports a relationship with Nord University that includes: travel reimbursement. Lucy J. Robertson reports a relationship with Norwegian Scientific Committee for Food Saftety that includes: travel reimbursement. LJR: Associate editor for FAWPAR. The other authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Author(s).)
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- 2024
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17. Gene expression profile of HCT-8 cells following single or co-infections with Cryptosporidium parvum and bovine coronavirus.
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Jiménez-Meléndez A, Shakya R, Markussen T, Robertson LJ, Myrmel M, and Makvandi-Nejad S
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- Animals, Cattle, Transcriptome, Cryptosporidium parvum genetics, Cryptosporidiosis parasitology, Cryptosporidium genetics, Coronavirus, Bovine genetics, Coinfection
- Abstract
Among the causative agents of neonatal diarrhoea in calves, two of the most prevalent are bovine coronavirus (BCoV) and the intracellular parasite Cryptosporidium parvum. Although several studies indicate that co-infections are associated with greater symptom severity, the host-pathogen interplay remains unresolved. Here, our main objective was to investigate the modulation of the transcriptome of HCT-8 cells during single and co-infections with BCoV and C. parvum. For this, HCT-8 cells were inoculated with (1) BCoV alone, (2) C. parvum alone, (3) BCoV and C. parvum simultaneously. After 24 and 72 h, cells were harvested and analyzed using high-throughput RNA sequencing. Following differential expression analysis, over 6000 differentially expressed genes (DEGs) were identified in virus-infected and co-exposed cells at 72 hpi, whereas only 52 DEGs were found in C. parvum-infected cells at the same time point. Pathway (KEGG) and gene ontology (GO) analysis showed that DEGs in the virus-infected and co-exposed cells were mostly associated with immune pathways (such as NF-κB, TNF-α or, IL-17), apoptosis and regulation of transcription, with a more limited effect exerted by C. parvum. Although the modulation observed in the co-infection was apparently dominated by the virus, over 800 DEGs were uniquely expressed in co-exposed cells at 72 hpi. Our findings provide insights on possible biomarkers associated with co-infection, which could be further explored using in vivo models., (© 2023. The Author(s).)
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- 2023
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18. Benzimidazole-resistance associated mutation in Haemonchus contortus in Norwegian sheep, as detected by droplet digital PCR.
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Gravdal M, Woolsey ID, Robertson LJ, Höglund J, Chartier C, and Stuen S
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- Animals, Sheep, Female, Benzimidazoles pharmacology, Polymerase Chain Reaction veterinary, Mutation, Haemonchus genetics, Anthelmintics pharmacology, Anthelmintics therapeutic use
- Abstract
The aim of this study was to investigate the occurrence of benzimidazole-resistant Haemonchus contortus in Norwegian sheep flocks. Screening was based on detection of one of the resistance-conferring mutations in the β tubulin isotype 1 gene (F200Y, TAC) in larvae (L3) cultivated from H. contortus eggs from naturally infected sheep. Faecal samples were collected in 2021/2022 from flocks in the northern (n = 34), central (n = 7), eastern (n = 40), southern (n = 1), and western (n = 87) areas of Norway. In total, samples were taken from 169 flocks (spring-ewes samples: 167, autumn-lambs samples: 134). Individual faecal samples were collected from 10 randomly selected ewes (spring) and 10 randomly selected lambs (autumn) in each flock. Faecal samples collected from each flock on each occasion were pooled (lamb and ewe samples pooled separately) and cultured for L3 development. After harvest of larvae (Baermann method), DNA was extracted and then analysed using droplet digital PCR with primer/probe sets targeting the BZ-associated F200Y (TAC) mutation. Haemonchus was found in 60% (80/134) of samples from lambs, and in 63% (106/167) from ewes. Among these, the F200Y mutation was detected in 73% (58/80) of larval samples from lambs and 69% (73/106) of larval samples from ewes, respectively. Although regional differences were evident, the mutation was detected in all areas indicating a widespread distribution and a strong potential for an increasing problem with treatment-resistant haemonchosis in Norwegian sheep flocks., Competing Interests: Declaration of Competing Interest None., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)
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- 2023
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19. Is there added value from using three serial samples when surveying the occurrence of intestinal parasites in children?
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Jerez Puebla LE, Núñez-Fernández FA, La Rosa Osoria E, Atencio Millán I, Cruz Rodríguez I, Rojas Rivero L, Fresco Sampedro Y, Rodríguez Moreno L, and Robertson LJ
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- Animals, Child, Humans, Cross-Sectional Studies, Feces parasitology, Prevalence, Parasites, Intestinal Diseases, Parasitic epidemiology, Intestinal Diseases, Parasitic parasitology, Giardia lamblia, Helminths
- Abstract
Background: Surveys for intestinal parasitic infections (IPIs) often involve samples from three sampling dates analysed by various microscopy techniques. However, analysis of three samples per individual is a huge burden on time and resources. We compared the value from analysing three or fewer samples., Methods: In this cross-sectional study, three faecal samples were collected every other day from 332 children from two locations in Guantanamo province, Cuba. Samples were analysed by wet mount with Lugol stain, Willis flotation method and Kato-Katz thick smear., Results: Most parasites were detected by wet mount, although helminth eggs not found by wet smear were detected by the Willis flotation method (in particular) and Kato-Katz smear. Blastocystis spp. was the most commonly detected parasite (about 65%), then Giardia duodenalis and then Entamoeba spp. Although analysis of two stool samples significantly increased occurrence data for Blastocystis, this was not so for the other parasites. For none of the protozoan parasites were results from analysing three samples significantly higher than results from analysing just two samples., Conclusions: Analysing two faecal samples by wet mount and the Willis flotation method provides useful data for estimating the prevalence of IPIs in relatively high prevalence settings. Analysing further samples provides limited additional information and adds an extra burden in terms of time and resources., (© The Author(s) 2023. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene.)
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- 2023
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20. Nothrus mite as a potential cause of exacerbation of pruritus in a cat.
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Kifleyohannes T, Olstad I, Jiménez-Meléndez A, Lambert EBJ, Ingvaldsen I, and Robertson LJ
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Objectives: Morphological and molecular approaches were used to identify arthropods associated with feline pruritus. The literature associated with the arthropod genus identified was reviewed., Methods: On two occasions (summer 2020 and summer 2021), the owner of a cat with seasonal pruritus (commenced 2020) found the cat's bed was substantially infested with arthropods suspected of being associated with exacerbated pruritus. The pruritus was largely itching and hair loss, particularly on the abdomen, and flaking skin patches. On the second occasion (2021), examples of the arthropods were sent to the parasitology laboratory at the Norwegian University of Life Sciences for identification. They were examined by stereomicroscopy and tentatively identified based on morphology. DNA was extracted, and identification confirmed by PCR and sequencing. The literature was reviewed to determine whether this arthropod genus has previously been considered to be associated with pruritus or the infestation of mammals., Results: Based on morphological characteristics, the arthropods were tentatively identified as Nothrus species mites. This was confirmed by PCR. A literature review found no previous reports of pruritus or other clinical signs associated with Nothrus species mites, and mites were not found on the cat. However, this mite has previously been found on small mammals at densities exceeding that expected of incidental stragglers., Conclusions and Relevance: The large number of Nothrus species mites could have exacerbated the cat's pruritus. By publishing this study, we hope to alert veterinarians to the possibility that Nothrus species mites may cause or exacerbate pruritus in cats., Competing Interests: The authors declared no potential conflicts of interest with respect to the research, authorship and/or publication of this article., (© The Author(s) 2023.)
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- 2023
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21. Bovine Enteroids as an In Vitro Model for Infection with Bovine Coronavirus.
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Shakya R, Jiménez-Meléndez A, Robertson LJ, and Myrmel M
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- Animals, Cattle, Ileum, Coronavirus, Bovine genetics, Coronavirus Infections, Cattle Diseases
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Bovine coronavirus (BCoV) is one of the major viral pathogens of cattle, responsible for economic losses and causing a substantial impact on animal welfare. Several in vitro 2D models have been used to investigate BCoV infection and its pathogenesis. However, 3D enteroids are likely to be a better model with which to investigate host-pathogen interactions. This study established bovine enteroids as an in vitro replication system for BCoV, and we compared the expression of selected genes during the BCoV infection of the enteroids with the expression previously described in HCT-8 cells. The enteroids were successfully established from bovine ileum and permissive to BCoV, as shown by a seven-fold increase in viral RNA after 72 h. Immunostaining of differentiation markers showed a mixed population of differentiated cells. Gene expression ratios at 72 h showed that pro-inflammatory responses such as IL-8 and IL-1A remained unchanged in response to BCoV infection. Expression of other immune genes, including CXCL-3, MMP13, and TNF-α, was significantly downregulated. This study shows that the bovine enteroids had a differentiated cell population and were permissive to BCoV. Further studies are necessary for a comparative analysis to determine whether enteroids are suitable in vitro models to study host responses during BCoV infection.
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- 2023
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22. Evaluation of the performance of a lateral flow device for quantitative detection of anti-SARS-CoV-2 IgG.
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Moore JS, Robertson LJ, Price R, Curry G, Farnan J, Black A, Nesbit MA, McLaughlin JA, and Moore T
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Introduction: The AbC-19™ lateral flow immunoassay (LFIA) performance was evaluated on plasma samples from a SARS-CoV-2 vaccination cohort, WHO international standards for anti-SARS-CoV-2 IgG (human), individuals ≥2 weeks from infection of RT-PCR confirmed SARS-CoV-2 genetic variants, as well as microorganism serology., Methods: Pre-vaccination to three weeks post-booster samples were collected from a cohort of 111 patients (including clinically extremely vulnerable patients) from Northern Ireland. All patients received Oxford-AstraZeneca COVID-19 vaccination for the first and second dose, and Pfizer-BioNTech for the third (first booster). WHO international standards, 15 samples from 2 variants of concern (Delta and Omicron) and cross-reactivity with plasma samples from other microorganism infections were also assessed on AbC-19™., Results: All 80 (100%) participants sampled post-booster had high positive IgG responses, compared to 38/95 (40%) participants at 6 months post-first vaccination. WHO standard results correlated with information from corresponding biological data sheets, and antibodies to all genetic variants were detected by LFIA. No cross-reactivity was found with exception of one (of five) Dengue virus samples., Conclusion: These findings suggest BNT162b2 booster vaccination enhanced humoral immunity to SARS-CoV-2 from pre-booster levels, and that this antibody response was detectable by the LFIA. In combination with cross-reactivity, standards and genetic variant results would suggest LFIA may be a cost-effective measure to assess SARS-CoV-2 antibody status., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Professor Tara Moore acted as a consultant for Abingdon Health during the final period of sampling. At time of conception and commencement of this study, none of the authors received payment from Abingdon Health., (© 2022 The Authors. Published by Elsevier Inc.)
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- 2022
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23. Foodborne and waterborne parasites at the 2020/2021 European Multicolloquium of Parasitology (EMOP).
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Robertson LJ and Romig T
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This Special Issue in Food and Waterborne Parasitology consists of six articles derived from presentations at the 13th European Multicolloquium of Parasitology (EMOP), that was held in Belgrade, Serbia in October 2021. Within the broad scope of parasitology presented at EMOP 2020/2021, the focus of several sessions, seminars, and presentations was on foodborne and waterborne parasites, with different aspects concerned with Cryptosporidium , Toxoplasma , Trichinella , and Opisthorchis all featuring. Although only a few manuscripts on foodborne and waterborne parasites are presented in this SI, the wide-ranging scope of the articles and, more broadly, of the presentations at EMOP 2020/2021, suggests that the topic of parasites transmitted by food and/or water remains of interest in the European parasitology community. We believe this is likely to be the case for years to come, and the topic is likely to feature prominently in the next (14th) EMOP, scheduled to be held in Poland in 2024. This interest, along with some obvious gaps in the articles on foodborne and waterborne parasites of both European and global importance (such as tapeworms, particularly Echinococcus spp. and Taenia solium ), suggests to us that another SI on the subject could be of value as an outcome of the 14th EMOP., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Lucy J Robertson reports a relationship with European Federation of Parasitologists that includes: board membership. Thomas Romig reports a relationship with European Federation of Parasitologists that includes: board membership. Both authors (Lucy Robertson and Thomas Romig) are GE for this SI - the manuscript is basically an editorial. In addition Lucy Robertson is an AE of this journal., (© 2022 The Author(s).)
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- 2022
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24. Oocyst Shedding Dynamics in Children with Cryptosporidiosis: a Prospective Clinical Case Series in Ethiopia.
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Johansen ØH, Abdissa A, Bjørang O, Zangenberg M, Sharew B, Alemu Y, Moyo S, Mekonnen Z, Langeland N, Robertson LJ, and Hanevik K
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- Animals, Child, Child, Preschool, Diarrhea epidemiology, Ethiopia epidemiology, Feces, Humans, Oocysts, Prospective Studies, Cryptosporidiosis diagnosis, Cryptosporidiosis drug therapy, Cryptosporidiosis epidemiology, Cryptosporidium, Malnutrition complications
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Knowledge on the duration of Cryptosporidium oocyst shedding, and how shedding may be affected by subtypes and clinical parameters, is limited. Reduced transmission may be a secondary benefit of cryptosporidiosis treatment in high-prevalence areas. We conducted a prospective clinical case series in children of <5 years presenting with diarrhea to a health center and a hospital in Ethiopia over an 18-month period. Stool samples were collected repeatedly from children diagnosed with cryptosporidiosis for up to 60 days. Samples were examined, and Cryptosporidium shedding was quantified, using auramine phenol, immunofluorescent antibody staining, and quantitative PCR (qPCR). In addition, species determination and subtyping were used to attempt to distinguish between new infections and ongoing shedding. Duration and quantity of shedding over time were estimated by time-to-event and quantitative models (sex- and age-adjusted). We also explored how diarrheal severity, acute malnutrition, and Cryptosporidium subtypes correlated with temporal shedding patterns. From 53 confirmed cryptosporidiosis cases, a median of 4 (range 1 to 5) follow-up stool samples were collected and tested for Cryptosporidium . The median duration of oocyst shedding was 31 days (95% confidence interval [CI], 26 to 36 days) after onset of diarrhea, with similar estimates from the quantitative models (31 days, 95% CI 27 to 37 days). Genotype shift occurred in 5 cases (9%). A 10-fold drop in quantity occurred per week for the first 4 weeks. Prolonged oocyst shedding is common in a pediatric clinical population with cryptosporidiosis. We suggest that future intervention trials should evaluate both clinical efficacy and total parasite shedding duration as trial endpoints. IMPORTANCE Cryptosporidiosis is an important cause of diarrhea, malnutrition, and deaths in young children in low-income countries. The infection spreads from person to person. After infection, prolonged release of the Cryptosporidium parasite in stool (shedding) may contribute to further spread of the disease. If diagnosis and treatment are made available, diarrhea will be treated and deaths will be reduced. An added benefit may be to reduce transmission to others. However, shedding duration and its characteristics in children is not well known. We therefore investigated the duration of shedding in a group of young children who sought health care for diarrhea in a hospital and health center in Ethiopia. The study followed 53 children with cryptosporidiosis for 2 months. We found that, on average, children released the parasite for 31 days after the diarrhea episode started. Point-of-care treatment of cryptosporidiosis may therefore reduce onward spread of the Cryptosporidium parasite within communities and households.
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- 2022
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25. Cryptosporidium and Giardia infections in humans in Tigray, Northern Ethiopia: an unexpectedly low occurrence of anthropozoonotic transmission.
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Kifleyohannes T, Nødtvedt A, Debenham JJ, Tysnes KR, Terefe G, and Robertson LJ
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- Animals, Child, Preschool, Diarrhea epidemiology, Ethiopia epidemiology, Feces parasitology, Giardia, Humans, Cryptosporidiosis epidemiology, Cryptosporidiosis parasitology, Cryptosporidium, Giardia lamblia genetics, Giardiasis parasitology
- Abstract
Enteric protozoans Cryptosporidium spp. and Giardia duodenalis are among the leading causes of diarrhoea in children. These parasites have particular impact in low- and middle-income countries. In these countries, people often live in close contact with their animals, highlighting the potential role of zoonotic routes of transmission in disease spread. The occurrence and species/genotypes of Cryptosporidium and Giardia duodenalis infecting humans in Tigray, Ethiopia were investigated, along with the risk associated with infection. Stool samples from 249 asymptomatic people (4-80 years of age) in four rural districts in Tigray and 58 from symptomatic young children (1-33 months) attending health centres in Mekelle, Tigray's main city, were analysed for Cryptosporidium oocysts and Giardia cysts. Participants in the rural areas completed questionnaires regarding potential risk factors, with emphasis on livestock contact and sources of water. The occurrence of Cryptosporidium infection was 6% and 5% in people in the rural districts and young children from Mekelle, respectively; equivalent figures for Giardia infection were 29% and 14%. Molecular characterization of Cryptosporidium isolates revealed C. ubiquitum, subtype XIIa in a sample from rural districts, and C. hominis subtype IdA17 (1 sample) and IbA9G3 (2 samples) in infants from Mekelle with diarrhoea. For Giardia, Assemblage B predominated (22/25; 88%), but we also identified three samples with Assemblage A (AII). Our major finding was that, despite the close contact between people and livestock in our rural study sites, transmission of Cryptosporidium and Giardia between humans and their animals seems to be surprisingly uncommon. Our results are discussed in relation to other relevant studies, and also draws attention to the possibility that introduction of zoonotic species and/or subtypes, such as C. parvum, could have serious consequences for both human and animal health. As our study was conducted in Tigray, further investigation in different settings in Ethiopia could provide relevant information on transmission and zoonotic potential, and the potential for spread of zoonotic transmission. In addition, given the importance of these two parasites in causing diarrhoea in children, this information is vital for developing effective appropriate interventions against transmission that can be applied not only in Tigray or Ethiopia, but throughout Africa and beyond., (Copyright © 2022 The Author(s). Published by Elsevier B.V. All rights reserved.)
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- 2022
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26. A comparison of risk factors for cryptosporidiosis and non-cryptosporidiosis diarrhoea: A case-case-control study in Ethiopian children.
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Johansen ØH, Abdissa A, Zangenberg M, Mekonnen Z, Eshetu B, Sharew B, Moyo S, Sommerfelt H, Langeland N, Robertson LJ, and Hanevik K
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- Case-Control Studies, Child, Child, Preschool, Diarrhea complications, Diarrhea epidemiology, Ethiopia epidemiology, Female, Humans, Infant, Risk Factors, Cryptosporidiosis complications, Cryptosporidiosis epidemiology, Cryptosporidium, Malnutrition complications
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Background: Cryptosporidiosis is a major cause of diarrhoea in young children in low-and-middle-income countries. New interventions should be informed by evidence pertaining to risk factors and their relative importance. Inconsistencies in the literature may to some extent be explained by choice of methodology, furthermore, most previous risk factor studies compared cryptosporidiosis cases to diarrhoea cases of other aetiologies rather than with controls without diarrhoea., Methodology/principal Findings: We investigated a broad set of factors in under-2-year-olds presenting with diarrhoea to a hospital and a health center in southwestern Ethiopia. We applied quantitative cut-offs to distinguish between cryptosporidiosis and incidental Cryptosporidium infection or carriage, a hierarchical causal framework to minimize confounding and overadjustment, and a case-case-control design, to describe risk factors for both cryptosporidiosis and non-cryptosporidiosis diarrhoea. Moderate and severe acute malnutrition were strongly associated with both cryptosporidiosis and non-cryptosporidiosis diarrhoea. Previous healthcare attendance and low maternal education were only associated with cryptosporidiosis, whereas unsafe child stool disposal, prematurity and early cessation of exclusive breastfeeding were significantly associated with non-cryptosporidiosis diarrhoea only. By estimation of population attributable fractions, socioeconomic factors-specifically low maternal education-and public tap water use, were apparently more important risk factors for cryptosporidiosis than for non-cryptosporidiosis diarrhoea., Conclusions/significance: Nutritional management of moderate acute malnutrition may be an effective intervention against cryptosporidiosis, particularly if combined with targeted therapy for cryptosporidiosis which, again, may mitigate nutritional insult. Focused caregiver education in healthcare settings and follow-up of children with acute malnutrition may prevent or improve outcomes of future episodes of cryptosporidiosis., Competing Interests: The authors have declared that no competing interests exist.
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- 2022
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27. Ready-to-eat salads and berry fruits purchased in Italy contaminated by Cryptosporidium spp., Giardia duodenalis, and Entamoeba histolytica.
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Barlaam A, Sannella AR, Ferrari N, Temesgen TT, Rinaldi L, Normanno G, Cacciò SM, Robertson LJ, and Giangaspero A
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- Feces, Fruit, Humans, Cryptosporidiosis, Cryptosporidium, Cysts, Entamoeba histolytica, Giardia lamblia, Giardiasis, Salads
- Abstract
Ready-to-eat (RTE) salads and berries are increasingly consumed in industrialized countries. These products can be contaminated by pathogenic parasites that have been responsible for foodborne outbreaks worldwide. In Italy, there are few data on contamination of RTE salads and berries with parasite transmission stages and this requires more-in-depth investigations. To estimate the prevalence of contamination with Cryptosporidium spp. and Giardia duodenalis in these fresh products, a total of 324 packages of local RTE mixed salads - belonging to three different industrial brands - and 324 packages of berries - blueberries from Peru, blackberries from Mexico, raspberries from Italy - were bought from supermarkets located in the Provinces of Bari and Foggia, Apulia, Italy. A pool size of nine packages was chosen and a total of 72 pools were processed in the whole year. After washing, the pellets were examined by microscopy (FLOTAC) and tested using conventional simplex PCR, targeting Cryptosporidium spp., Giardia duodenalis, and Entamoeba spp., and sequencing. Several Cryptosporidium species and Giardia duodenalis assemblages, some of which are of potential zoonotic relevance, as well as Entamoeba spp., were identified in both matrices. By microscopy, Giardia-like cysts in local raspberries and Entamoeba-like cysts in imported blueberries were detected. Giardia duodenalis (Assemblages A, B and E) and Entamoeba histolytica were molecularly confirmed with overall prevalences of 4.6% (95% C.I. 3.0-6.8) and 1% (95% C.I. 0.3-2.1), respectively. Molecular methods identified Cryptosporidium ryanae, Cryptosporidium bovis, Cryptosporidium xiaoi, and Cryptosporidium ubiquitum in both matrices, with a prevalence of 5.1% (95% C.I. 3.3-7.3). A distinct seasonality in prevalence was observed for G. duodenalis, with most positives occurring in spring, whereas Cryptosporidium showed no significant seasonal variations. These results highlight that inadequate management of fresh produce, both locally produced and imported, along the food chain may have the potential for consequences on human health., (Copyright © 2022 Elsevier B.V. All rights reserved.)
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- 2022
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28. Surveillance of berries sold on the Norwegian market for parasite contamination using molecular methods.
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Temesgen TT, Stigum VM, and Robertson LJ
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- Animals, Fruit parasitology, Cryptosporidiosis, Cryptosporidium genetics, Cyclospora genetics, Parasites genetics
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The risk of foodborne parasite infection linked to the consumption of contaminated fresh produce has long been known. However, despite epidemiological links between the outbreaks and contaminated berries, few studies have assessed the magnitude of parasite contamination on fresh produce sold in Europe. The present study was aimed to address the knowledge gap on parasite contamination of berries sold in Norway. Samples of blueberries, strawberries, and raspberries were analysed by multiplex qPCR for detection of Echinococcus multilocularis, Toxoplasma gondii, and Cyclospora cayetanensis. In addition, a simplex qPCR method was employed for detecting contamination of the berries with Cryptosporidium spp. A total of 820 samples of berries, each of around 30 g (274 samples of blueberries, 276 samples of raspberries, and 270 samples of strawberries), were analysed. We found an overall occurrence of 2.9%, 6.6%, and 8.3% for T. gondii, C. cayetanensis, and Cryptosporidium spp., respectively, whereas E. multilocularis was not detected from any of the samples investigated. Strawberries and raspberries were most often contaminated with Cryptosporidium spp., whereas blueberries were contaminated mostly with C. cayetanensis. Detection of parasite contaminants on fresh berries indicates the need for a system to ensure the parasitological safety of fresh berries., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)
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- 2022
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29. Transition to PCR diagnosis of cryptosporidiosis and giardiasis in the Norwegian healthcare system: could the increase in reported cases be due to higher sensitivity or a change in the testing algorithm?
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Campbell SM, Pettersen FO, Brekke H, Hanevik K, and Robertson LJ
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- Algorithms, Delivery of Health Care, Feces parasitology, Humans, Polymerase Chain Reaction, Cryptosporidiosis diagnosis, Cryptosporidiosis parasitology, Cryptosporidium genetics, Giardiasis diagnosis, Giardiasis parasitology
- Abstract
Cryptosporidiosis has been a notifiable infection in Norway since 2012 and giardiasis since 1977. For both infections, there has been an increase in notified cases. We used a questionnaire to explore whether this may be associated with implementation of molecular diagnostic methods. We received responses from 14 of 16 laboratories, most of which had implemented molecular diagnostic methods for these parasites. Algorithms for testing had also been modified, and several laboratories now test more faecal samples than previously for both parasites. The increase in reported cases may reflect not only higher sensitivity of diagnostic methods, but also more sample testing., (© 2022. The Author(s).)
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- 2022
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30. IgG antibody production and persistence to 6 months following SARS-CoV-2 vaccination: A Northern Ireland observational study.
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Robertson LJ, Price R, Moore JS, Curry G, Farnan J, Black A, Blighe K, Nesbit MA, McLaughlin JAD, and Moore T
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- Antibodies, Viral, COVID-19 Vaccines, Humans, Immunoglobulin G, Middle Aged, Northern Ireland, SARS-CoV-2, Vaccination, Antibody Formation, COVID-19 prevention & control
- Abstract
Background: This study evaluates spike protein IgG antibody response following Oxford-AstraZeneca COVID-19 vaccination using the AbC-19™ lateral flow device., Methods: Plasma samples were collected from n = 111 individuals from Northern Ireland. The majority were >50 years old and/or clinically vulnerable. Samples were taken at five timepoints from pre-vaccination until 6-months post-first dose., Results: 20.3% of participants had detectable IgG responses pre-vaccination, indicating prior COVID-19. Antibodies were detected in 86.9% of participants three weeks after the first vaccine dose, falling to 74.7% immediately prior to the second dose, and rising to 99% three weeks post-second vaccine. At 6-months post-first dose, this decreased to 90.5%. At all timepoints, previously infected participants had significantly higher antibody levels than those not previously infected., Conclusion: This study demonstrates that strong anti-spike protein antibody responses are evoked in almost all individuals that receive two doses of Oxford-AstraZeneca vaccine, and which largely persist beyond six months after first vaccination., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Professor Tara Moore acted as a consultant for Abingdon Health during the final period of sampling. At time of conception and commencement of this study, none of the authors received payment from Abingdon Health., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)
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- 2022
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31. Interactions between Cryptosporidium parvum and bovine corona virus during sequential and simultaneous infection of HCT-8 cells.
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Shakya R, Meléndez AJ, Robertson LJ, and Myrmel M
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- Animals, Cattle, Cell Line, Tumor, Feces, Horses, Humans, Cattle Diseases, Coinfection, Coronavirus, Bovine, Cryptosporidiosis, Cryptosporidium, Cryptosporidium parvum, Viruses
- Abstract
Neonatal diarrhoea in calves is one of the major health problems in the cattle industry. Although co-infections are often associated with greater severity of disease, there is limited information on any impact on the pathogens themselves. Herein, we studied Cryptosporidium parvum and bovine coronavirus (BCoV) in human HCT-8 cells, inoculated either sequentially or simultaneously, to investigate any influence from the co-infections. Quantitative results from (RT)-qPCR showed that prior inoculation with either of the two pathogens had no influence on the other. However, the results from simultaneous co-inoculation showed that entry of viral particles was higher when C. parvum sporozoites were present, although elevated virus copy numbers were no longer evident after 24 h. The attachment of BCoV to the sporozoites was probably due to specific binding, as investigations with bovine norovirus or equine herpes virus-1 showed no attachment between sporozoites and these viruses. Flow cytometry results at 72 h post inoculation revealed that C. parvum and BCoV infected 1-11% and 10-20% of the HCT-8 cells, respectively, with only 0.04% of individual cells showing double infections. The results from confocal microscopy corroborated those results, showing an increase in foci of infection from 24 to 72 h post inoculation for both pathogens, but with few double infected cells., Competing Interests: Declaration of competing interest The authors declare that they have no conflicts of interest., (Copyright © 2021 The Author(s). Published by Elsevier Masson SAS.. All rights reserved.)
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- 2022
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32. User experience of home-based AbC-19 SARS-CoV-2 antibody rapid lateral flow immunoassay test.
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Jing M, Bond R, Robertson LJ, Moore J, Kowalczyk A, Price R, Burns W, Nesbit MA, McLaughlin J, and Moore T
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- Adolescent, Adult, Aged, Child, Female, Humans, Immunoassay, Male, Middle Aged, Antibodies, Viral immunology, COVID-19 diagnosis, COVID-19 epidemiology, COVID-19 immunology, COVID-19 Serological Testing, Pandemics, Point-of-Care Testing, SARS-CoV-2 immunology
- Abstract
The urgent need to scale up testing capacity during the COVID-19 pandemic has prompted the rapid development of point-of-care diagnostic tools such as lateral flow immunoassays (LFIA) for large-scale community-based rapid testing. However, studies of how the general public perform when using LFIA tests in different environmental settings are scarce. This user experience (UX) study of 264 participants in Northern Ireland aimed to gather a better understanding of how self-administered LFIA tests were performed by the general public at home. The UX performance was assessed via analysis of a post-test questionnaire including 30 polar questions and 11 7-point Likert scale questions, which covers the multidimensional aspects of UX in terms of ease of use, effectiveness, efficiency, accuracy and satisfaction. Results show that 96.6% of participants completed the test with an overall average UX score of 95.27% [95% confidence interval (CI) 92.71-97.83%], which suggests a good degree of user experience and effectiveness. Efficiency was assessed based on the use of physical resources and human support received, together with the mental effort of self-administering the test measured via NASA Task Load Index (TLX). The results for six TLX subscales show that the participants scored the test highest for mental demand and lowest for physical demand, but the average TLX score suggests that the general public have a relatively low level of mental workload when using LFIA self-testing at home. Five printed LFIA testing results (i.e. the 'simulated' results) were used as the ground truth to assess the participant's performance in interpreting the test results. The overall agreement (accuracy) was 80.63% [95% CI 75.21-86.05%] with a Kappa score 0.67 [95% CI 0.58-0.75] indicating substantial agreement. The users scored lower in confidence when interpreting test results that were weak positive cases (due to the relatively low signal intensity in the test-line) compared to strong positive cases. The end-users also found that the kit was easier to use than they expected (p < 0.001) and 231 of 264 (87.5%) reported that the test kit would meet their requirements if they needed an antibody testing kit. The overall findings provide an insight into the opportunities for improving the design of self-administered SARS-CoV-2 antibody testing kits for the general public and to inform protocols for future UX studies of LFIA rapid test kits., (© 2022. The Author(s).)
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- 2022
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33. Cryptosporidium and Giardia in Livestock in Tigray, Northern Ethiopia and Associated Risk Factors for Infection: A Cross-Sectional Study.
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Kifleyohannes T, Nødtvedt A, Debenham JJ, Terefe G, and Robertson LJ
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The occurrence and species/genotypes of Cryptosporidium and Giardia duodenalis infecting young livestock in selected districts of Tigray, Ethiopia were investigated, along with risks associated with infection. A total of 757 faecal samples were collected from calves, lambs, and goat kids from four rural districts in Tigray, and also from calves in periurban Mekelle, Tigray's main city, and analysed for Cryptosporidium oocysts and Giardia cysts. Farmers answered questionnaires regarding potential risk factors at sample collection. Immunofluorescent antibody staining was used for parasite detection, and PCR at selected genes and sequencing of positive samples was used for molecular characterisation. The occurrence of Cryptosporidium infection was 10, 9, and 4% in calves, lambs, and goat kids, respectively; equivalent figures for Giardia infection were 39, 32, and 21%. Molecular characterisation of Cryptosporidium isolates revealed C. ubiquitum , subtype XIIa in all three host species; C. ryanae in calves and goat kids; C. andersoni and C. bovis were identified only in calves, and C. xiaoi was identified in lambs. For Giardia , Assemblage E predominated in all host species, but among calf isolates we also identified a few potentially zoonotic genotypes (assemblages A (AI) and Assemblage B). Periparturient care was shown to be a particularly relevant risk factor for infection, and infections were less likely to occur under extensive management systems. Our major findings were widespread occurrence of both parasites in livestock, and the apparent lack of the most common zoonotic species. Our results are discussed in relation to other relevant studies. As our study was conducted in Tigray, further investigation in different settings in Ethiopia could provide relevant information on transmission and zoonotic potential. In addition, given the dependency on healthy animals for the livelihoods of the population of Tigray, investigation of the effect of these common parasites on livestock productivity is important., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Kifleyohannes, Nødtvedt, Debenham, Terefe and Robertson.)
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- 2022
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34. Identification of two potential aetiological agents of chronic diarrhoea in an immunocompromised patient in Cuba using conventional and molecular diagnostic techniques.
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Jerez Puebla LE, Núñez Fernández FA, Atencio Millán I, Pérez Avila J, Fraga Nodarse J, Cruz Rodríguez I, Rodríguez Moreno L, Fresco Sampedro Y, and Robertson LJ
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- Adult, Anti-Infective Agents therapeutic use, Coccidiosis drug therapy, Cuba, Diarrhea microbiology, Diarrhea parasitology, Enterocytozoon genetics, HIV Infections complications, HIV Infections drug therapy, Humans, Immunocompromised Host, Male, Microsporidiosis drug therapy, Molecular Diagnostic Techniques, Polymerase Chain Reaction, Sarcocystidae genetics, Sarcoma, Kaposi complications, Sarcoma, Kaposi drug therapy, Trimethoprim, Sulfamethoxazole Drug Combination therapeutic use, Coccidiosis diagnosis, Diarrhea diagnosis, Enterocytozoon isolation & purification, Microsporidiosis diagnosis, Sarcocystidae isolation & purification
- Abstract
The aetiology of diarrhoea in a patient in Cuba with HIV was investigated. Although molecular diagnostics are still not used in many under-resourced settings, here traditional methods were supported by use of PCR. This approach enabled detection of a dual infection (Cystoisospora belli and Enterocytozoon bieneusi), the latter of which was not identified by microscopy with Didier's trichromic staining., (Copyright © 2021 The Author(s). Published by Elsevier B.V. All rights reserved.)
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- 2022
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35. Gastrointestinal nematodes and Fasciola hepatica in Norwegian cattle herds: a questionnaire to investigate farmers' perceptions and control strategies.
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Opsal T, Toftaker I, Nødtvedt A, Robertson LJ, Tysnes KR, Woolsey I, and Hektoen L
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- Animals, Cattle, Farmers, Female, Gastrointestinal Tract, Humans, Surveys and Questionnaires, Fasciola hepatica, Nematoda
- Abstract
Background: Pasture management influences the prevalence and impact of the pasture parasites (PP) in cattle herds, which cause production-limiting disease worldwide. Evaluating farmer management strategies is vital when considering sustainable PP control practices. The aim of this questionnaire-based study was to describe the pasture management and control strategies regarding PP in Norwegian beef cattle (BC) and dairy cattle (DC) production systems with a focus on gastrointestinal nematodes (GIN) and Fasciola hepatica., Results: A total of 745 responses from BC (return rate 20.5%) and 1347 responses from DC farmers (30.7%) were included. The mean total pasture time for DC was 4.2 months for first-season grazers and 4.3 months for second-season grazers and cows, while the corresponding finding in BC was 5.4 months. Home pasture was used for most of the pasture period, particularly for first-season grazer dairy heifers (81%), which were also commonly grazed on the same pasture every year (79%). For most farmers it was necessary for grazing areas to be used for cattle for more than one season (77% of BC farmers and 89% of DC farmers). However, changing the pasture during the season was common in both DC (67%) and BC (70%) herds. The majority of DC farmers (60%) stated that they did not consider that they had a problem with PP. Of the remaining 40%, few respondents could specify whether their herds had a problem due to infection by GIN (11%) or liver flukes (12%). Treatment for GIN was performed by 52% of DC and 34% of BC farmers. Diagnostic faecal samples were collected upon suspicion of parasitic disease by 5% of DC and 16% of BC farmers. Veterinarians were stated as a central source of information about parasite management and treatment., Conclusions: Potential risks for exposure to PP were identified, such as use of the same pasture every year for first-season grazers and frequent use of home pasture. The perception of problems related to PP appeared low. Regular anthelmintic treatment without concurrent use of diagnostic faecal samples seems to be common practice., (© 2021. The Author(s).)
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- 2021
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36. A retrospective study of Taenia spp. in Cuban patients: what does molecular analysis tell us?
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Jerez Puebla LE, Núñez Fernández FA, Fraga Nodarse J, Cordovi Prado R, Atencio Millán I, Cruz Rodríguez I, Fimia Duarte R, Sánchez Romero MDC, Ortega Medina SC, Del Risco U, Pérez Santos L, and Robertson LJ
- Abstract
Taeniosis is a neglected disease, particularly in developing countries, and is caused by infection with the adult tapeworm of either Taenia solium, Taenia saginata , and Taenia asiatica . Of these, T. solium is of primary concern due to the potential for cysticercosis should T. solium eggs be ingested. In Cuba, all cases of taeniosis are assumed to be caused by T. saginata , although some cases of cysticercosis have been documented. It is therefore important to gain further insights regarding the species causing taeniosis in Cuba, especially as diagnostic records indicate an increasing incidence, with the highest number of cases reported in 2020. In this study, we analysed 37 Taenia -positive faecal samples (or proglottids isolated from faecal samples) from the period 2001 until 2020 from all regions of the country. Genomic DNA was extracted from the samples, which had been stored in 10% formalin, using the QIAamp Tissue Kit. Species identification was carried out by duplex real-time PCR targeting the mitochondrial DNA. All cases were found to be T. saginata, and sequence analysis of three isolates confirmed the identification of this species. Our data do not provide any evidence that T. solium currently occurs in Cuba. However, given the relatively low number of samples analysed here, that the parasite may be imported with visitors or travellers who have been in endemic countries, and that taeniosis has relatively mild symptoms and thus infected patients may not seek medical attention, we recommend species determination for all taeniosis cases reported in Cuba., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2021 The Authors.)
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- 2021
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37. Mosquito control at a tertiary teaching hospital in Nigeria.
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Efunshile AM, Ojide CK, Igwe D, Onyia B, Jokelainen P, and Robertson LJ
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Background: Mosquitoes are vectors of numerous diseases, including malaria and yellow fever. Mosquito control is therefore a priority in many countries, especially in healthcare settings. Here we investigated the opinions of patients and staff regarding mosquito control at a hospital in Nigeria, and also gathered data on mosquito-control measures in this setting., Methods: We conducted a cross-sectional questionnaire study of staff and patients and an observational approach to obtain data on mosquito-control measures used at a tertiary teaching hospital in Abakaliki, Nigeria., Discussion: Both staff (N=517) and patients (N=302) reported experiencing more mosquito bites at the hospital than elsewhere. As well as contributing to discomfort, this exposure may put hospital staff and patients at risk of mosquito-borne infections. Complaints from patients about mosquitoes were reported by over 90% of staff, and over 50% of staff respondents were aware of patient discharge against medical advice due to mosquitoes. The most common control method was killing mosquitoes by hand. We observed a lack of door screens in all wards, window screens were absent or torn, and most beds did not have nets. In the children's wards none of the beds had nets., Conclusions: Current measures against mosquitoes in this hospital appeared inadequate, and healthcare staff and hospital patients may be at increased risk of mosquito-borne infections. Mosquito control in the hospital requires attention, and the needs for improvement in mosquito control in the healthcare setting more widely should be evaluated and addressed., (© 2021 The Authors.)
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- 2021
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38. Contamination of fresh produce sold on the Italian market with Cyclospora cayetanensis and Echinococcus multilocularis.
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Barlaam A, Temesgen TT, Tysnes KR, Rinaldi L, Ferrari N, Sannella AR, Normanno G, Cacciò SM, Robertson LJ, and Giangaspero A
- Subjects
- Animals, Blueberry Plants parasitology, Cyclospora genetics, Cyclospora isolation & purification, Echinococcus multilocularis genetics, Echinococcus multilocularis isolation & purification, Italy, Mexico, Oocysts genetics, Oocysts isolation & purification, Rubus parasitology, Toxoplasma genetics, Toxoplasma growth & development, Toxoplasma isolation & purification, Cyclospora growth & development, Echinococcus multilocularis growth & development, Fast Foods parasitology, Food Contamination analysis, Fruit parasitology
- Abstract
To investigate the presence of Cyclospora cayetanensis, Toxoplasma gondii and Echinococcus spp. in fresh produce sold in Italy, 324 locally produced 'ready-to-eat' (RTE) mixed-salad packages belonging to three brands and 324 berries packages (blueberries and blackberries imported from Peru and Mexico, respectively, and raspberries grown in Italy) were purchased at retail. Nine individual packages from each of the six types of fresh produce were collected monthly for one year, and with the same produce pooled, this resulted in a total of 72 pools for the whole year. Using microscopy (FLOTAC), a Cyclospora-like oocyst was detected in a blueberry sample and a taeniid egg was detected in a RTE-salad sample. Molecular tools confirmed these to be C. cayetanensis and Echinococcus multilocularis, respectively. Toxoplasma gondii was not detected in any of the samples. This study shows for the first time in Europe that imported berries on the Italian market may be contaminated with C. cayetanensis and RTE salads grown in Italy with E. multilocularis. The results indicate a new epidemiological scenario and highlight that current management of fresh produce, locally produced or imported, does not ensure products are free from parasite contamination., (Copyright © 2021. Published by Elsevier Ltd.)
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- 2021
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39. Is Fresh Produce in Tigray, Ethiopia a Potential Transmission Vehicle for Cryptosporidium and Giardia ?
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Kifleyohannes T, Debenham JJ, and Robertson LJ
- Abstract
In rural Ethiopia, where people often share their homes with their livestock, infections of humans and animals with Cryptosporidium and Giardia are relatively common. One possible transmission route is consumption of contaminated fresh produce; this study investigated the occurrence of Cryptosporidium and Giardia in fresh produce in four districts of rural Tigray in Ethiopia. Fresh produce samples ( n = 55) were analysed using standard laboratory procedures. Overall, 15% (8/55) of samples were found to be contaminated. Although contamination levels were mostly low, a few samples had high numbers of Giardia cysts (up to around 70 cysts per 30 g sample). Molecular analyses were largely unsuccessful, but Giardia Assemblage A was identified in one sample. Contamination with these parasites was identified in two of the four districts, but, although a similar pattern has already been described for water contamination, this may be at least partially explained by sampling bias. Nevertheless, we speculate that access to clean water sources may be an important factor for reducing the occurrence of these pathogens. Given the public health and veterinary burden associated with both parasites, the factors which are of importance for their circulation in the communities and environments deserve further investigation.
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- 2021
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40. Use of Oxidative Stress Responses to Determine the Efficacy of Inactivation Treatments on Cryptosporidium Oocysts.
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Temesgen TT, Tysnes KR, and Robertson LJ
- Abstract
Cryptosporidium oocysts are known for being very robust, and their prolonged survival in the environment has resulted in outbreaks of cryptosporidiosis associated with the consumption of contaminated water or food. Although inactivation methods used for drinking water treatment, such as UV irradiation, can inactivate Cryptosporidium oocysts, they are not necessarily suitable for use with other environmental matrices, such as food. In order to identify alternative ways to inactivate Cryptosporidium oocysts, improved methods for viability assessment are needed. Here we describe a proof of concept for a novel approach for determining how effective inactivation treatments are at killing pathogens, such as the parasite Cryptosporidium. RNA sequencing was used to identify potential up-regulated target genes induced by oxidative stress, and a reverse transcription quantitative PCR (RT-qPCR) protocol was developed to assess their up-regulation following exposure to different induction treatments. Accordingly, RT-qPCR protocols targeting thioredoxin and Cryptosporidium oocyst wall protein 7 (COWP7) genes were evaluated on mixtures of viable and inactivated oocysts, and on oocysts subjected to various potential inactivation treatments such as freezing and chlorination. The results from the present proof-of-concept experiments indicate that this could be a useful tool in efforts towards assessing potential technologies for inactivating Cryptosporidium in different environmental matrices. Furthermore, this approach could also be used for similar investigations with other pathogens.
- Published
- 2021
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41. User experience analysis of AbC-19 Rapid Test via lateral flow immunoassays for self-administrated SARS-CoV-2 antibody testing.
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Jing M, Bond R, Robertson LJ, Moore J, Kowalczyk A, Price R, Burns W, Nesbit MA, McLaughlin J, and Moore T
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- Adolescent, Adult, Antibodies, Viral immunology, Child, Educational Status, Female, Humans, Male, Middle Aged, Patient Satisfaction, Point-of-Care Systems, Self Administration, Sensitivity and Specificity, Young Adult, Antibodies, Viral analysis, COVID-19 Testing statistics & numerical data, Immunoassay statistics & numerical data
- Abstract
Lateral flow immunoassays are low cost, rapid and highly efficacious point-of-care devices, which have been used for SARS-CoV-2 antibody testing by professionals. However, there is a lack of understanding about how self-administered tests are used by the general public for mass testing in different environmental settings. The purpose of this study was to assess the user experience (UX) (including usability) of a self-testing kit to identify COVID-19 antibodies used by a representative sample of the public in their cars, which included 1544 participants in Northern Ireland. The results based on 5-point Likert ratings from a post-test questionnaire achieved an average UX score of 96.03% [95% confidence interval (CI) 95.05-97.01%], suggesting a good degree of user experience. The results of the Wilcoxon rank sum tests suggest that UX scores were independent of the user's age and education level although the confidence in this conclusion could be strengthened by including more participants aged younger than 18 and those with only primary or secondary education. The agreement between the test result as interpreted by the participant and the researcher was 95.85% [95% CI 94.85-96.85%], Kappa score 0.75 [95% CI 0.69-0.81] (indicating substantial agreement). Text analysis via the latent Dirichlet allocation model for the free text responses in the survey suggest that the user experience could be improved for blood-sample collection, by modifying the method of sample transfer to the test device and giving clearer instructions on how to interpret the test results. The overall findings provide an insight into the opportunities for improving the design of SARS-CoV-2 antibody testing kits to be used by the general public and therefore inform protocols for future user experience studies of point-of-care tests.
- Published
- 2021
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42. Evaluation of the IgG antibody response to SARS CoV-2 infection and performance of a lateral flow immunoassay: cross-sectional and longitudinal analysis over 11 months.
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Robertson LJ, Moore JS, Blighe K, Ng KY, Quinn N, Jennings F, Warnock G, Sharpe P, Clarke M, Maguire K, Rainey S, Price RK, Burns WP, Kowalczyk AM, Awuah A, McNamee SE, Wallace GE, Hunter D, Sager S, Chao Shern C, Nesbit MA, McLaughlin JAD, and Moore T
- Subjects
- Antibodies, Viral, Antibody Formation, Cross-Sectional Studies, Humans, Immunization, Passive, Immunoassay, Northern Ireland epidemiology, SARS-CoV-2, Sensitivity and Specificity, Spike Glycoprotein, Coronavirus, COVID-19 Serotherapy, COVID-19 therapy, Immunoglobulin G
- Abstract
Objective: To evaluate the dynamics and longevity of the humoral immune response to SARS-CoV-2 infection and assess the performance of professional use of the UK-RTC AbC-19 Rapid Test lateral flow immunoassay (LFIA) for the target condition of SARS-CoV-2 spike protein IgG antibodies., Design: Nationwide serological study., Setting: Northern Ireland, UK, May 2020-February 2021., Participants: Plasma samples were collected from a diverse cohort of individuals from the general public (n=279), Northern Ireland healthcare workers (n=195), pre-pandemic blood donations and research studies (n=223) and through a convalescent plasma programme (n=183). Plasma donors (n=101) were followed with sequential samples over 11 months post-symptom onset., Main Outcome Measures: SARS-CoV-2 antibody levels in plasma samples using Roche Elecsys Anti-SARS-CoV-2 IgG/IgA/IgM, Abbott SARS-CoV-2 IgG and EuroImmun IgG SARS-CoV-2 ELISA immunoassays over time. UK-RTC AbC-19 LFIA sensitivity and specificity, estimated using a three-reference standard system to establish a characterised panel of 330 positive and 488 negative SARS-CoV-2 IgG samples., Results: We detected persistence of SARS-CoV-2 IgG antibodies for up to 10 months post-infection, across a minimum of two laboratory immunoassays. On the known positive cohort, the UK-RTC AbC-19 LFIA showed a sensitivity of 97.58% (95.28% to 98.95%) and on known negatives, showed specificity of 99.59% (98.53 % to 99.95%)., Conclusions: Through comprehensive analysis of a cohort of pre-pandemic and pandemic individuals, we show detectable levels of IgG antibodies, lasting over 46 weeks when assessed by EuroImmun ELISA, providing insight to antibody levels at later time points post-infection. We show good laboratory validation performance metrics for the AbC-19 rapid test for SARS-CoV-2 spike protein IgG antibody detection in a laboratory-based setting., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)
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- 2021
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43. Strengthening of district mental health services in Gauteng Province, South Africa.
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Robertson LJ, Moosa MYH, and Jeenah FY
- Subjects
- Advisory Committees, Human Rights, Humans, Organizations, South Africa, Delivery of Health Care organization & administration, Health Policy, Health Services Accessibility, Mental Health Services organization & administration, Public Health Practice
- Abstract
In response to the Life Esidimeni tragedy, the Gauteng Department of Health established a task team to advise on the implementation of the Health Ombud's recommendations and to develop a mental health recovery plan. Consistent with international human rights and South African legislation and policy, the plan focused on making mental healthcare more accessible, incorporating a strategy to strengthen district mental health services to deliver community-based care for people with any type and severity of mental illness. The strategy included an organogram with three new human resource teams integrated into the district health system: a district specialist mental health team to develop a public mental health approach, a clinical community psychiatry team for service delivery, and a team to support non-governmental organisation governance. This article discusses the strategy in terms of guiding policies and legislation, the roles and responsibilities of the various teams in the proposed organogram, and its sustainability.
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- 2021
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44. Performance and operational feasibility of two diagnostic tests for cryptosporidiosis in children (CRYPTO-POC): a clinical, prospective, diagnostic accuracy study.
- Author
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Johansen ØH, Abdissa A, Zangenberg M, Mekonnen Z, Eshetu B, Bjørang O, Alemu Y, Sharew B, Langeland N, Robertson LJ, and Hanevik K
- Subjects
- Child, Cryptosporidium, Databases, Factual, Ethiopia, Feasibility Studies, Feces microbiology, Humans, Immunoassay, Prospective Studies, Real-Time Polymerase Chain Reaction, Sensitivity and Specificity, Cryptosporidiosis diagnosis, Diagnostic Tests, Routine, Diarrhea diagnosis
- Abstract
Background: Cryptosporidiosis is a common cause of diarrhoea in young children (aged younger than 24 months) in low-resource settings but is currently challenging to diagnose. Light-emitting diode fluorescence microscopy with auramine-phenol staining (LED-AP), recommended for tuberculosis testing, can also detect Cryptosporidium species. A lateral-flow test not requiring refrigerator storage (by contrast with most immunochromatographic lateral-flow assays) has also recently been developed for Cryptosporidium spp detection. We aimed to evaluate the diagnostic accuracy and operational feasibility of LED-AP and the lateral-flow test strip for cryptosporidiosis in children., Methods: We did a prospective diagnostic accuracy study in two health-care facilities in Ethiopia, in a consecutive series of children younger than 5 years of age with diarrhoea (three or more loose stools within the previous 24 h) or dysentery (at least one loose stool with stains of blood within the previous 24 h). Stool samples were tested for Cryptosporidium spp by LED-AP and the lateral-flow test strip; accuracy of each test was estimated by independent and blind comparison with a composite reference standard comprising quantitative immunofluorescent antibody test (qIFAT), ELISA, and quantitative PCR (qPCR). Quantitative cutoff values for diarrhoea-associated infection were established in an embedded case-control substudy, with cases of cryptosporidiosis coming from the 15 districts in and around Jimma and the eight districts surrounding Serbo, and community controls without diarrhoea in the previous 48 h recruited by weekly frequency matching by geographical district of the household, age group, and enrolment week., Findings: Stool samples from 912 children with diarrhoea or dysentery and 706 controls from the case-control substudy were tested between Dec 22, 2016, and July 6, 2018. Estimated reference-standard cutoff values for cryptosporidiosis positivity were 2·3 × 10
5 DNA copies per g of wet stool for qPCR, and 725 oocysts per g for qIFAT. LED-AP had a sensitivity for cryptosporidiosis of 88% (95% CI 79-94; 66 of 75 samples) and a specificity of 99% (98-99; 717 of 726 samples); the lateral-flow test strip had a sensitivity of 89% (79-94; 63 of 71 samples) and a specificity of 99% (97-99; 626 of 635 samples)., Interpretation: LED-AP has high sensitivity and specificity for cryptosporidiosis and should be considered as a dual-use technology that can be easily integrated with existing laboratory infrastructures in low-resource settings. The lateral-flow test strip has similar sensitivity and specificity and provides an alternative that does not require microscopy, although purchase cost of the test strip is unknown as it is not yet available on the market., Funding: Norwegian Research Council GLOBVAC fund, The Bill & Melinda Gates Foundation, Norwegian Society for Medical Microbiology, University of Bergen, and Vestfold Hospital Trust., (Copyright © 2021 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)- Published
- 2021
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45. Formal Comment; Tracing the source of infection of cystic and alveolar echinococcosis, neglected parasitic infections with long latency: The shaky road of "evidence" gathering.
- Author
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Torgerson PR and Robertson LJ
- Subjects
- Animals, Echinococcosis epidemiology, Echinococcus, Parasitic Diseases
- Abstract
Competing Interests: The authors have declared that no competing interests exist.
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- 2021
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46. Occurrence of faecal endoparasites in reindeer (Rangifer tarandus) in two grazing areas in northern Norway.
- Author
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Idland L, Juul AM, Solevåg EK, Tysnes KR, Robertson LJ, and Utaaker KS
- Subjects
- Animal Husbandry, Animals, Cryptosporidiosis parasitology, Feces parasitology, Intestinal Diseases, Parasitic epidemiology, Intestinal Diseases, Parasitic parasitology, Norway epidemiology, Prevalence, Cryptosporidiosis epidemiology, Cryptosporidium isolation & purification, Intestinal Diseases, Parasitic veterinary, Reindeer
- Abstract
Background: Semi-domesticated reindeer represent an important livestock industry and livelihood for a proportion of the human population in northern Fennoscandia. Reindeer husbandry is considered an extensive animal husbandry, where the animals are kept mostly on natural pastures, although sometimes kept in fenced areas for shorter periods. These reindeer may harbour a variety of parasites that may affect animal health and production. The relatively limited close contact between herds and owners gives limited opportunities for diagnosis and treatment of diseases in general. Furthermore, the effects of subclinical parasitism in livestock are commonly expressed as a reduction in productivity rather than clinical disease and mortality. Thus, specific knowledge of endoparasites and parasitic infections in these herds is scarce. This study investigated the occurrence of various endoparasites in reindeer by analysis of a total of 114 faecal samples from winter-slaughtered reindeer from two different grazing areas in Troms and Finnmark, Norway., Results: Using a McMaster method, a Baermann technique, and a direct immunofluorescent antibody test, the following parasites were identified in the faecal samples with the occurrence data given as percentages: Strongylid eggs (62%), Nematodirinae spp. eggs (24%), Capillaria sp. eggs (42%) and Moniezia spp. eggs (17%), Dictyocaulus spp. larvae (14%) protostrongylid larvae (40%), Eimera spp. oocysts (23%), and Giardia duodenalis cysts (5%). Cryptosporidium oocysts were not detected. Parasite eggs, oocysts, and cysts were quantified. Molecular analysis revealed G. duodenalis sub-assemblage AI, a potentially zoonotic genotype not previously reported in reindeer from this region. Morphological analyses of Eimeria oocysts identified two species, Eimeria mayeri and Eimeria rangiferis, and molecular analyses of the cytochrome C oxidase I (coi) gene and 18 s rRNA (18SSU) gene of Eimeria confirmed the presence of Eimeria species that are specific to reindeer., Conclusions: A high prevalence, but low burden, of endoparasites was detected in samples from these semi-domesticated reindeer. The samples were collected during winter, when adult gastrointestinal parasites usually produce only low numbers of transmission stages. Therefore, together with the low number of samples, detailed and definitive conclusions regarding parasite status of semi-domesticated reindeer are avoided. Nevertheless, these data provide a snapshot overview of parasite occurrence in a semi-domesticated animal group vulnerable to the various environmental changes to which they are exposed.
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- 2021
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47. Global Goat! Is the Expanding Goat Population an Important Reservoir of Cryptosporidium ?
- Author
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Utaaker KS, Chaudhary S, Kifleyohannes T, and Robertson LJ
- Abstract
Goats are a primary or additional income source for many families in resource-poor areas. Although often considered inferior to other livestock, the resilience of goats and their ability to thrive in a range of environments means that that they are of particular value. Furthermore, goats emit less methane than other livestock species. In these same areas, it is well-documented that cryptosporidiosis has a substantial impact on infant morbidity and mortality, as well as reducing child growth and development. As Cryptosporidium also causes diarrheal disease in goats, the question arises whether goats may represent a reservoir of infection to humans. Epidemiological studies regarding the potential for transmission of Cryptosporidium between goats and humans have largely concluded that Cryptosporidium species infecting goats are not zoonotic. However, these studies are mostly from developed countries, where goat husbandry is smaller, management routines differ greatly from those of developing countries, contact between goats and their owners is more limited, and cryptosporidiosis has less impact on human health. In this article, background information on goat husbandry in different countries is provided, along with information on Cryptosporidium prevalence among goats, at both the species and sub-species levels, and the potential for zoonotic transmission. The intention is to indicate data gaps that should be filled and to increase awareness of the role of goats as providers for low-income families, often living in areas where cryptosporidiosis is endemic and where appropriate baseline interventions could have a positive impact, regardless of species of goat or parasite., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Utaaker, Chaudhary, Kifleyohannes and Robertson.)
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- 2021
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48. Removal of Parasite Transmission Stages from Berries Using Washing Procedures Suitable for Consumers.
- Author
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Temesgen TT, Robertson LJ, Stigum VM, and Tysnes KR
- Abstract
Due to the delicate nature of berries and the reduced shelf-life once washed, producers usually do not wash berries. Therefore, consumers are expected to wash the berries prior to consumption, and this might be a more effective way of infection prevention. However, the efficacy of consumer berry-washing procedures in removing the parasite contaminants from the berries surface has not been investigated. The aim of the present study was, therefore, to compare the efficacy of three different washing techniques in removing parasite contaminants. Three alternatives to washing berries before consumption were compared on berries artificially contaminated with oo/cysts of Cyclospora cayetanensis , Cryptosporidium parvum , and Giardia duodenalis . The results show that simple washing of berries under the cold tap for 1 min could remove on average at least 80% of the parasites, except for C. cayetanensis , which seems to be stickier than both G. duodenalis and C. parvum . The percent removal was slightly lower for raspberries as compared to blueberries. Although the differences are expected, a relevant result of the study is that washing contaminated berries prior to consumption by the consumer removes a considerable proportion of parasites and thereby lowers the risk of ingesting parasites' transmission stages.
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- 2021
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49. Surveillance of foodborne parasitic diseases in Europe in a One Health approach.
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van der Giessen J, Deksne G, Gómez-Morales MA, Troell K, Gomes J, Sotiraki S, Rozycki M, Kucsera I, Djurković-Djaković O, and Robertson LJ
- Abstract
In 2012, WHO/FAO ranked 24 foodborne parasites (FBP) using multicriteria decision analysis (MCDA) to provide risk assessors with a basis for prioritising control of highly ranked FBP on the global level. One conclusion was that ranking may differ substantially per region. In Europe, the same methodology was used to rank FBP of relevance for Europe. Of the 24 FBP, the top-five prioritised FBP were identified for Europe as Echinococcus multilocularis , Toxoplasma gondii , Trichinella spiralis , E. granulosus , and Cryptosporidium spp., all of which are zoonotic. The objective of the present study was to provide an overview of surveillance and reporting systems in Europe for these top five prioritised FBP in the human and animal populations, to identify gaps, and give recommendations for improvement. Information on the surveillance systems was collected from 35 European countries and analysed according to the five different regions. For most FBP, human surveillance is passive in most countries and regions in Europe and notification differs between countries and regions. Adequate surveillance programmes for these FBP are lacking, except for T. spiralis , which is notifiable in 34 countries with active surveillance in susceptible animals under EU directive. Although human and animal surveillance data are available for the five prioritised FBP, we identified a lack of consistency in surveillance and reporting requirements between national experts and European bodies. Recommendations for improved surveillance systems are discussed., Competing Interests: Authors declare that they have no conflict of interest., (© 2021 The Authors. Published by Elsevier Ltd on behalf of World Federation of Parasitologists.)
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- 2021
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50. Mental illness: South Africa's blind spot.
- Author
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Robertson LJ
- Subjects
- Humans, Politics, South Africa epidemiology, Mental Disorders epidemiology
- Published
- 2021
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