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Theodor Hiepe (1929-2022) was an outstanding researcher, a world-renowned scientist, a dedicated teacher and a great mentor. During his scientific career, which spanned over 60 years, he made major contributions to many different fields of parasitology. With the passing of Dr. h.c. mult. Theodor Hiepe in September 2022 the scientific community suffered a great loss. [ABSTRACT FROM AUTHOR]

Biorepositories are an important resource for today's research. To obtain more scientific information, stored samples from older repositories are being investigated using modern techniques and technologies, while new repositories are being built to facilitate genomic studies. Parasitological research has progressed from basic laboratory procedures to using molecular and genomic methodologies to understand parasite biology, necessitating the creation of parasitology-based biorepositories. Parasite biorepositories can reduce the cost of frequent sampling in resource-constrained situations and enhance best research practices, in addition to enhancing research productivity. Repositories can also help to prevent the loss of biological materials from uncommon, endangered, or newly found species. In Nigeria, the available repositories are mostly for the archiving of clinical samples. To promote parasite genomics research in Nigeria, a parasite library is required. Through membership, institutional, and international support, national groups such as the Parasitology and Public Health Society of Nigeria (PPSN) can build and maintain parasite biorepositories. [ABSTRACT FROM AUTHOR]

Objective. To determine the presence of Perkinsus sp. in the sand clam Chionista fluctifraga cultivated in an intertidal zone of the southeastern Gulf of California, using Ray's thioglycollate fluid medium staining (MFTR) and polymerase chain reaction (PCR). Material and Methods. The prevalence and parasite load of Perkinsus sp. were monthly obtained and correlated with environmental water conditions and clam biometric indicators (n=540), from May 2018 to September 2019. Results. Presumptive hypnospores of the protozoan were detected in eight months of culture. The prevalence fluctuated from 3.3% to 13.3%, while the average parasite load ranged from 2 to 1286 hypnospores/g of tissue. The intensity of infection varied from negative to light. The prevalence and parasite load were correlated with each other (r=0.61, p<0.05) but not with the environmental parameters, nor with the biometric indicators of the clam. The PCR test was negative for the MFTR positive cases. Conclusions. Presumptive hypnospores of Perkinsus sp. were detected in C. fluctifraga without clear indications of infection that compromised the clam health in culture. The constant monitoring of Perkinsus sp. in C. fluctifraga is highly recommended to establish possible infections. [ABSTRACT FROM AUTHOR]

The isopods of the family Cymothoidae are ectoparasites crustaceans that infest a wide variety of saltwater fish. This paper documented the first occurrence of Nerocila acuminata (Schiödte & Meinert, 1881) parasitizing the shortnose guitarfish Zapteryx brevirostris (Müller & Henle, 1841) (Rhinobatiformes, Rhinobatidae) in the southern Atlantic Ocean. This report can be an available tool to create a parasitology database for a species of conservation interest. It will also provide scientific data that can help the understanding of the biological factors acting in healthy populations and thus support the efforts made to preserve and conserve the species. [ABSTRACT FROM AUTHOR]

Cutaneous leishmaniasis is a continually spreading health problem in Amhara Region, Ethiopia. Despite this, up- to-date information on referral laboratory facility has been not yet reported. Therefore, this study was aimed at reporting up-to-date information about eight year's cutaneous leishmaniasis trend status. Data on referred cases from 2013 to 2020 were collected at Amhara Public Health Institute Parasitology department by reviewing log book. Of the 243 suspected cases, 114 (46.9%) were positive (confirmed) with microscope and cultured results showed that most of them were negatives. Most of the suspected cases were from 16 to 30 years and males by age and sex, respectively. Trend status by year depicted that largest numbers of suspected and confirmed cases were reported in 2013, 2015, and 2019 years. Finally, the trend status by zone showed that most cases were reported from South Gondar and Awi zones, respectively. [ABSTRACT FROM AUTHOR]

The number of reported macrocyclic lactones (ML) resistance cases across all livestock hosts is steadily increasing. Different studies in the parasitic nematode Haemonchus contortus assume the participation of cytochrome P450s (Cyps) enzymes in ML resistance. Still, functional data about their individual contribution to resistance or substrate specificity is missing. Via microinjection, transgenic Caenorhabditis elegans expressing HCON_00141052 (transgene-Hco-cyp-13A11) from extrachromosomal arrays were generated. After 24 h of exposure to different concentrations of ivermectin (IVM), ivermectin aglycone (IVMa), selamectin (SEL), doramectin (DRM), eprinomectin (EPR), and moxidectin (MOX), motility assays were performed to determine the impact of the H. contortus Cyp to the susceptibility of the worms against each ML. While transgene-Hco-cyp-13A11 significantly decreased susceptibility to IVM (four-fold), IVMa (2-fold), and SEL (3-fold), a slight effect for DRM and no effect for MOX, and EPR was observed. This substrate specificity of Hco-cyp-13A11 could not be explained by molecular modeling and docking studies. Hco-Cyp-13A11 molecular models were obtained for alleles from isolates with different resistance statuses. Although 14 amino acid polymorphisms were detected, none was resistance specific. In conclusion, Hco-cyp-13A11 decreased IVM, IVMa, and SEL susceptibility to a different extent, but its potential impact on ML resistance is not driven by polymorphisms. [ABSTRACT FROM AUTHOR]

Different methods for detecting Plasmodium parasite infection or exposure are available, but a systematic comparison of all these methodologies to predict malaria infection is lacking. Understanding the characteristics of respective tests is helpful in choosing the most appropriate tests for epidemiological or research purposes. We performed microscopy, rapid diagnostic tests (RDTs), and polymerase chain reaction (PCR) for 496 patients presenting with febrile illness in Dakar, Senegal, in 2015. Blood samples had laboratory multiplex assays performed for Immunoglobin G serology and detection of histidine-rich protein 2 (HRP2) antigen. Sensitivity (Se) and specificity (Sp) for different tests were calculated using PCR as the gold standard for detecting active infection. Modeling through latent class analysis compared each test to a modeled gold standard for Se/Sp estimates. Against PCR, Se/Sp were 95.2%/93.7% for RDT, 90.4%/100.0% for microscopy, and 97.9%/48.1% for laboratory HRP2 detection. Compared with the modeled gold standard, Se of microscopy was 93.5% and Se of RDT, PCR, and laboratory HRP2 detection were all greater than 99%. Se/Sp of Immunoglobin G serology were substantially lower for detecting active infection. Compared with single tests, a combinatorial latent class analysis approach of multiple biomarkers for detecting malaria infection from patient samples provides greater sensitivity and specificity for epidemiological estimates and research objectives. [ABSTRACT FROM AUTHOR]

Intellectually disabled individuals are more prone to parasitic infections due to their unusual behaviors, immune and nutrient deficiencies, and living conditions. The current study is aimed at evaluating the prevalence of intestinal parasites in institutionalized intellectually disabled individuals in Bandar Abbas County in the south of Iran. Subjects of the study were 119 individuals, living in an intellectually disabled individual care center. Demographic features of the subjects including age, sex, intellectual disability type, and duration of their stay in the center were recorded. A stool sample was taken from each subject and evaluated by direct wet mount and formalin-ethyl-acetate concentration methods. Samples were also examined, using trichrome and modified acid-fast permanent staining. The mean age of the subjects was 27.6 (±2.24), ranging from 4 to 60 years old. Of the 119 participants, 55 (46.2%) were male, and 64 cases (53.8%) were female. Overall, 31 individuals (26.1%, 95% CI: 18.4-34.9) were found to be infected with at least one type of intestinal parasite. Blastocystis hominis, as the most common detected parasite, was detected in 13 (10.1%), Entamoeba coli in 12 (10.1%), Giardia lamblia in 5 (4.2%), Cryptosporidium in 2 (1.7%), Iodamoeba butchlii in 2 (1.7%), and Endolimax nana in 1 (0.8%) of participants. Three cases had coinfection with Blastocystis hominis and Entamoeba coli, one case was infected with Blastocystis hominis and Giardia lamblia, and one case was coinfected with Giardia lamblia and Entamoeba coli. There were no statistically significant associations between intestinal parasitic infection and gender, age, type of intellectual disability, or duration of stay in the care center (P > 0.05). The findings of the present study indicate a relatively high prevalence of parasitic infections in people with intellectual disabilities in Bandar Abbas, southern Iran. Noteworthy is the high prevalence of Blastocyst and also the presence of Cryptosporidium infection in these people. Periodic treatment of these people and improvement of their maintenance conditions can be considered for the prevention and control of intestinal parasitic infection in these people. [ABSTRACT FROM AUTHOR]

Objective: parasites are organisms that live inside or on another species for their own benefit, managing to affect plants, animals, and humans. Children are more vulnerable to infection, but the incidence has decreased thanks to the improvement in Costa Rican sanitation. The aim was to evaluate the general knowledge that the Costa Rican population has regarding childhood parasitosis. Methodology: an observational, descriptive, cross-sectional study was carried out on a sample of 196 subjects. A survey was conducted among Costa Ricans over 18 years of age who had a device with internet access. The participants were asked about their knowledge on the clinical picture of childhood parasitosis in Costa Rica. Results: most of the participants were college students (68.3%). 89.9% of them believe that pet parasites can infect humans. The best-known parasites were lice, marked by 173 (88.3%) people. The stomach is the part of the body considered most affected, with 148 (75.5%) responses. The main known preventive measure is washing hands with soap and water, answered by 133 participants (67.9%). Conclusion: Many participants believe that humans can be infected by the same parasites as animals. Lice were the best known and ticks the least. Most of the people consider vomiting and/or diarrhea as one of the main symptoms and believe that the stomach is the most affected part during the infection. In addition, they consider that the main preventive measure to avoid contagion is hand washing. [ABSTRACT FROM AUTHOR]

In the last three years, the economic, social and health situation of the whole world has been deeply tested and not at all predictable. The way of life imposed by Covid-19 changed the paradigm of many human activities, of which education could not be an exception.Taken by surprise, at a very low level of digitization of teaching-learning activities, Romania has suddenly switched to online education. Thus, the use of platforms such as Zoom Video Communications or Microsoft Teams for teaching and moreover, avoided the freezing of the school and university year.The use of applications in support of learning, such as books creator, random cards or random wheel, have also proved their usefulness for consolidating knowledge of veterinary pharmacology. [ABSTRACT FROM AUTHOR]

The revolution in genomics has enabled large‐scale population genetic investigations of a wide range of organisms, but there has been a relatively limited focus on improving analytical pipelines. To efficiently analyse large data sets, highly integrated and automated software pipelines, which are easy to use, efficient, reliable, reproducible and run in multiple computational environments, are required. A number of software workflows have been developed to handle and process such data sets for population genetic analyses, but effective, specialized pipelines for genetic and statistical analyses of nonmodel organisms are lacking. For most species, resources for variomes (sets of genetic variations found in populations of species) are not available, and/or genome assemblies are often incomplete and fragmented, complicating the selection of the most suitable reference genome when multiple assemblies are available. Additionally, the biological samples used often contain extraneous DNA from sources other than the species under investigation (e.g., microbial contamination), which needs to be removed prior to genetic analyses. For these reasons, we established a new pipeline, called Escalibur, which includes: functionalities, such as data trimming and mapping; selection of a suitable reference genome; removal of contaminating read data; recalibration of base calls; and variant‐calling. Escalibur uses a proven gatk variant caller and workflow description language (WDL), and is, therefore, a highly efficient and scalable pipeline for the genome‐wide identification of nucleotide variation in eukaryotes. This pipeline is available at https://gitlab.unimelb.edu.au/bioscience/escalibur (version 0.3‐beta) and is essentially applicable to any prokaryote or eukaryote. [ABSTRACT FROM AUTHOR]

Land disturbances caused by urban development modify and create novel habitats with novel ecological pressures, which in turn may negatively affect remaining wildlife populations, e.g. by altering interspecific interactions. However, it is not clear whether these modified interactions, e.g. parasitism, affect urban wildlife negatively. This is especially true for reptiles, as even parasitism under natural conditions is understudied in this group. We have observed that up to 35% of grass snakes (Natrix natrix) are infected with the trematode Leptophallus nigrovenosus in urban areas of Kraków, while none of snakes sampled in nearby suburban and non-urban forests exhibited this infection. As this trematode typically inhabits the intestine, we suggest that its occurrence in the oral cavity may be a sign of very high infection rates. However, we did not detect any negative effects of observed infection on body size, mass and body condition of affected individuals. On the other hand, competition with other parasite species in suburban and non-urban habitats may be responsible for not detecting L. nigrovenosus in grass snakes from these sites. Nevertheless, interpretation of our findings is difficult, as knowledge on L. nigrovenosus biology is very limited. Our study underlines the necessity to fill the research gap in reptile parasitology. [ABSTRACT FROM AUTHOR]

Background: Malaria is one of the leading causes of death worldwide caused by parasites of the genus Plasmodium. The reduced efficacy of the mainstay antimalarial drugs due to the widespread of drug-resistant Plasmodium falciparum (P. falciparum) necessitates an effort to develop novel antimalarial drugs with new targets. The effects of a phenolic compound, ellagic acid, against the malaria parasite have previously been reported. This present study aimed to evaluate the effect of ellagic acid on pH of the P. falciparum digestive vacuole. Methods: The antimalarial potential of ellagic acid against the chloroquine-sensitive strain (3D7) of P. falciparum was assessed by using a malarial SYBR Green 1 fluorescence-based (MSF) assay. The effect of different concentrations of ellagic acid on the pH of the parasite's digestive vacuole at mid-trophozoite stage was examined by using a ratiometric pH indicator, fluorescein isothiocyanate (FITC)-dextran on the flow cytometry. Results: The result of the MSF assay showed that ellagic acid has an antimalarial activity (half-maximal inhibitory concentration [IC50] = 1.85 ± 4.57 nM) at par with a standard drug, artemisinin (IC50 = 1.91 ± 5.41 nM). The pH of the digestive vacuole of ellagic acid-treated parasites was significantly changed (pH values ranged from 6.11 to 6.74) in a concentration-dependent manner as compared to untreated parasites (P < 0.001). A similar effect was shown by the parasites treated with a standard proton pump inhibitor, concanamycin A. Conclusion: These findings suggest that ellagic acid might have altered the digestive vacuole pH through the inhibition of proton pumps that regulate the acidification of this organelle. Overall, this study provides a valuable insight into the potential of ellagic acid as a promising antimalarial candidate with a novel mechanism of action. [ABSTRACT FROM AUTHOR]

The objective of the present study is to assess the growth performance, health condition, natural food intake, muscle fiber profile and isotopic composition of tambaqui, reared for 56 days in different production systems. Tambaqui fish (1.18 ± 0.55 g; 4.49 ± 0.66 cm) were stocked in 600 m2 earthen ponds (P), 3.6 m3 cages within earthen ponds (CP) and 15.68 m3 cages in a large water reservoir (C), at densities of 9 fish m−2 in P and 170 fish m−3 in C and CP. After 28 days of culture, the weight of fish reared in CP was lower than those in P and in C, with no difference between fish in P and C. Low water dissolved oxygen concentrations and, consequently, reduced growth were observed in fish reared in P from day 28. By day 56, fish in C presented high final weight (57.19 g). Best feed conversion ratio was observed in C (0.92) and CP (0.95), with no difference between these two treatments. Survival rate was not affected by the production systems. Zooplankton corresponded to 1.47%, 19.23% and 9.11% of δ13C assimilated by fish reared in C, CP and P, respectively. Increased mean abundance of monogeneans was observed in all treatments. >70% of fish reared in C presented fin damage, whereas in P and CP it was of 5% and 25%, respectively. After 56 days, cortisol concentration was higher in fish reared in C. Albumin, cholesterol, and total proteins were higher in fish reared in P. Muscle fiber hyperplasia (diameter < 30 μm) was predominant in fish in all treatments. Based on the results, tambaqui may be produces in cages and ponds. However, ponds demand more attention to avoid opportunistic fish entrance and to control parasitic infestations and water oxygen levels. • Intensification during the nursery phase of tambaqui does not affect performance negatively. • Natural food contributes to the muscle growth of tambaqui in intensive systems. • High contribution of natural food for the growth of tambaqui shows pond may be beneficial to low trophic level fish species. • Fish physiology can be challenged by the high stocking density in cages, causing more fin damage and high cortisol levels. • Fish reared in ponds are challenged by poor water quality, which in turn reduces growth and may increase parasitic load. [ABSTRACT FROM AUTHOR]

Battery poultry houses are subject to infestations by pests, such as the ectoparasitic mites Dermanyssus gallinae (De Geer, 1778) and Ornithonyssus bursa (Berlese, 1888) which are hematophagous and can cause skin lesions, stress, and even death of hens, leading to significant economic losses. Recent European studies have shown that these mites can also work as vectors of pathogenic microorganisms. Therefore, due to the absence of records on the association between D. gallinae and O. bursa and pathogenic microorganisms in Brazil, the present study aimed to identify pathogenic bacteria through a metagenomics analysis associated with mites collected from a poultry house located in a rural area of the state of Rio Grande do Sul and direct from a skin’ person that lives in a farm in the interior of the state of São Paulo (Brazil). For the material collected in Rio Grande do Sul, a higher predominance of endosymbiotic bacteria, and different species of the pathogenic bacteria species Bartonella was observed. On the other hand, some enterobacteria were identified from O. bursa samples, but the amount was not high enough to identify the species. Additionally, the endosymbiotic Wolbachia spp. was identified in both O. bursa samples (pooled and individuals). Besides the detection of Wolbachia, in the individual O. bursa microbiome, we detected Spiroplasma spp. and ‘Candidatus Cardinium’. This is the first time that a microbiome study has been made for the species D. gallinae and O. bursa in Brazil, as well as the first time that Wolbachia, Spiroplasma and ‘Candidatus Cardinium’ was detected in O. bursa samples. [ABSTRACT FROM AUTHOR]

Popular conceptions of the relationship between science and religion often emphasize the mutual compatibility but segregation of these two authoritative domains. However, along the uncertain border between these two spheres exist many questions that appear to influence and be influenced by both scientific and theological evidence. For biologists, the gruesome details of parasite biology and behavior illuminate a shadow in nature where science and theology must intersect—did a loving creator God design parasites? Here, I explore the writings and experiments of the early fathers of parasitology who established and matured a new scientific discipline while deeply integrating their theological beliefs with their scientific investigations. I argue that modern scientists can, and often should, follow in the footsteps of our scientific forefathers and intentionally allow our theological presuppositions to inspire scientific experiments, especially in these important boundary‐crossing subjects. In doing so, I believe we may advance scientific understanding of the way reality is by asking unexpected questions and uncover deeper truths about the character of God as revealed in his intricately complex and eternally fascinating creation. [ABSTRACT FROM AUTHOR]

The sheep body louse (Bovicola ovis) commonly referred to as sheep lice are small chewing ectoparasites of sheep. Infection results in significant economic costs to the Australian sheep industry due to reduced wool quality caused by chronic itching from sheep rubbing and biting fleece. Treatment relies on use of insecticides; however, resistance has developed against pyrethroid and other insect growth regulator lousicides. There is urgent need to develop cost-effective lice management to reduce the use of insecticides, with the application of insecticidal treatments only applied when an infestation is detected. However, the current detection method relies on fleece parting for detection of B. ovis which is highly dependent on the skill of the inspector, the number of sheep examined, and the prevalence and severity of the infestation. To improve B. ovis detection, a highly sensitive (5 × 10−8 ng/μL) and specific multiplex quantitative PCR which simultaneously detects sheep lice and sheep DNA was developed. In addition, a B. ovis loop-mediated isothermal amplification (LAMP) assay was developed for field use. The B. ovis LAMP (Bov-LAMP) assay was optimized to reliably detect B. ovis from wool samples down to 5 × 10−6 ng/μL, with time to positive (Tp) < 10 min. Both assays demonstrate high sensitivity and specificity, enabling rapid identification of B. ovis DNA from sheep fleece samples and have the capacity to be used for ongoing management and surveillance of B. ovis in Australian sheep flocks. [ABSTRACT FROM AUTHOR]

Background Information on human filariasis in international travelers is scarce. We describe the epidemiology, clinical presentation, and outcome of these infections in a reference travel clinic over the past decades. Methods We reviewed all cases of filariasis diagnosed at the Institute of Tropical Medicine, Antwerp, Belgium, from 1994 to 2018. Diagnosis was obtained by either parasitological methods (confirmed) or strict clinical case definitions (probable). We assessed the characteristics of cases at diagnosis and response to therapy within 3–12 months. Results A total of 320 patients (median age: 41 years; 71% males) were diagnosed with 327 filarial infections (Wuchereria bancrofti = 6, Onchocerca volvulus = 33, Loa loa = 150, Mansonella perstans = 130, unspecified species = 8). Diagnosis was confirmed in 213/320 (67%) patients. European long-term travelers accounted for 166 patients (52%) and visitors/migrants from tropical countries for another 110 (34%). Central Africa was the likely region of acquisition for 294 (92%) patients. The number of filariasis cases decreased from 21.5/year on average in the 1990s to 6.3/year in the past decade, when loiasis became predominant. Cases reported symptoms in >80% of all filarial infections but mansonellosis (45/123 single infections; 37%). Lymphatic filariasis and onchocerciasis cases responded well to conventional therapy. However, 30% of patients with loiasis and mansonellosis experienced treatment failure (with diethylcarbamazine and levamisole-mebendazole, respectively). Conclusions The burden and species distribution of filariasis in travelers evolved in the past decades. Most presentations were symptomatic. Case management would benefit from more effective therapies for loiasis and mansonellosis. [ABSTRACT FROM AUTHOR]

Background: A central question in parasitology is why parasites mature and reproduce in some host species but not in others. Yet, a better understanding of the inability of parasites to complete their life cycles in less suitable hosts may hold clues for their control. To shed light on the molecular basis of parasite (non-)maturation, we analyzed transcriptomes of thorny-headed worms (Acanthocephala: Pomphorhynchus laevis), and compared developmentally arrested worms excised from European eel (Anguilla anguilla) to developmentally unrestricted worms from barbel (Barbus barbus). Results: Based on 20 RNA-Seq datasets, we demonstrate that transcriptomic profiles are more similar between P. laevis males and females from eel than between their counterparts from barbel. Impairment of sexual phenotype development was reflected in gene ontology enrichment analyses of genes having differential transcript abundances. Genes having reproduction- and energy-related annotations were found to be affected by parasitizing either eel or barbel. According to this, the molecular machinery of male and female acanthocephalans from the eel is less tailored to reproduction and more to coping with the less suitable environment provided by this host. The pattern was reversed in their counterparts from the definitive host, barbel. Conclusions: Comparative analysis of transcriptomes of developmentally arrested and reproducing parasites elucidates the challenges parasites encounter in hosts which are unsuitable for maturation and reproduction. By studying a gonochoric species, we were also able to highlight sex-specific traits. In fact, transcriptomic evidence for energy shortage in female acanthocephalans associates with their larger body size. Thus, energy metabolism and glycolysis should be promising targets for the treatment of acanthocephaliasis. Although inherently enabling a higher resolution in heterosexuals, the comparison of parasites from definitive hosts and less suitable hosts, in which the parasites merely survive, should be applicable to hermaphroditic helminths. This may open new perspectives in the control of other helminth pathogens of humans and livestock. [ABSTRACT FROM AUTHOR]

Background Cipargamin (KAE609) is a potent antimalarial in a phase II trial. Here we report efficacy, pharmacokinetics, and resistance marker analysis across a range of cipargamin doses. These were secondary endpoints from a study primarily conducted to assess the hepatic safety of cipargamin (hepatic safety data are reported elsewhere). Methods This phase II, multicenter, randomized, open-label, dose-escalation trial was conducted in sub-Saharan Africa in adults with uncomplicated Plasmodium falciparum malaria. Cipargamin monotherapy was given as single doses up to 150 mg or up to 50 mg once daily for 3 days, with artemether-lumefantrine as control. Key efficacy endpoints were parasite clearance time (PCT), and polymerase chain reaction (PCR)–corrected and uncorrected adequate clinical and parasitological response (ACPR) at 14 and 28 days. Pharmacokinetics and molecular markers of drug resistance were also assessed. Results All single or multiple cipargamin doses ≥50 mg were associated with rapid parasite clearance, with median PCT of 8 hours versus 24 hours for artemether-lumefantrine. PCR-corrected ACPR at 14 and 28 days was >75% and 65%, respectively, for each cipargamin dose. A treatment-emerging mutation in the Pfatp4 gene, G358S, was detected in 65% of treatment failures. Pharmacokinetic parameters were consistent with previous data, and approximately dose proportional. Conclusions Cipargamin, at single doses of 50 to 150 mg, was associated with very rapid parasite clearance, PCR-corrected ACPR at 28 days of >65% in adults with uncomplicated P. falciparum malaria, and recrudescent parasites frequently harbored a treatment-emerging mutation. Cipargamin will be further developed with a suitable combination partner. Clinical Trials Registration ClinicalTrials.gov (NCT03334747). [ABSTRACT FROM AUTHOR]

Background: Annual mass drug administrations (MDA) of ivermectin will strongly reduce Onchocerca volvulus microfilariae (mf) in the skin and in the onchocerciasis patients' eyes. Ivermectin treatment will also affect the expression of immunity in patients, such that activated immune defenses may help control and contribute to clearance of mf of O. volvulus. Longitudinal surveys are a prerequisite to determining the impact of ivermectin on the status of anti-parasite immunity, notably in risk zones where parasite transmission and active O. volvulus infections persist. Methodology/Principal findings: Onchocerciasis patients were treated annually with ivermectin and their Onchocerca volvulus antigen (OvAg) specific IgG and cellular responses were investigated before and at 30 years post initial ivermectin treatment (30yPT). Repeated annual ivermectin treatments eliminated persisting O. volvulus microfilariae (mf) from the skin of patients and abrogated patent infections. The OvAg-specific IgG1 and IgG4 responses were diminished at 30yPT to the levels observed in endemic controls. Prior to starting ivermectin treatment, OvAg-induced cellular productions of IL-10, IFN-γ, CCL13, CCL17 and CCL18 were low in patients, and at 30yPT, cellular cytokine and chemokine responses increased to the levels observed in endemic controls. In contrast, mitogen(PHA)- induced IL-10, IFN-γ, CCL17 and CCL18 cellular production was diminished. This divergent response profile thus revealed increased parasite antigen-specific but reduced polyclonal cellular responsiveness in patients. The transmission of O. volvulus continued at the patients' location in the Mô river basin in central Togo 2018 and 2019 when 0.58% and 0.45%, respectively, of Simulium damnosum s.l. vector blackflies carried O. volvulus infections. Conclusions/Significance: Repeated annual ivermectin treatment of onchocerciasis patients durably inhibited their patent O. volvulus infections despite ongoing low-level parasite transmission in the study area. Repeated MDA with ivermectin affects the expression of immunity in patients. O. volvulus parasite-specific antibody levels diminished to levels seen in infection-free endemic controls. With low antibody levels, antibody-dependent cellular cytotoxic responses against tissue-dwelling O. volvulus larvae will weaken. O. volvulus antigen inducible cytokine and chemokine production increased in treated mf-negative patients, while their innate responsiveness to mitogen declined. Such lower innate responsiveness in elderly patients could contribute to reduced adaptive immune responses to parasite infections and vaccines. On the other hand, increased specific cellular chemokine responses in mf-negative onchocerciasis patients could reflect effector cell activation against tissue invasive larval stages of O. volvulus. The annual Simulium damnosum s.l. biting rate observed in the Mô river basin was similar to levels prior to initiation of MDA with ivermectin, and the positive rtPCR results reported here confirm ongoing O. volvulus transmission. Author summary: Onchocerciasis is a neglected tropical disease, and a major cause of debilitating skin disease and ocular damage that can lead to irreversible blindness. Annual mass drug administrations (MDA) of ivermectin strongly reduces the load of Onchocerca volvulus microfilaria (mf) in the skin and in the patients' eyes. Evolution of onchocerciasis as a disease is prevented by MDA, but recent studies have shown that O. volvulus transmission has not been completely interrupted. Repeated MDA with ivermectin affects immune responses, such that activated immune defenses may enhance clearance of mf of O. volvulus. Longitudinal surveys are required to determine the impact of ivermectin on the status of immunity, notably in risk zones where parasite transmission and active O. volvulus infections persist. We examined the changes of O. volvulus parasite-specific antibody and cellular immune responsiveness in patients treated annually with ivermectin for 30 years. Treatment prevented patent O. volvulus infections, whilst parasite antigen-specific cytokine and chemokine responses increased but O.volvulus-specific antibody responses declined. Such decreased antibody levels could weaken antibody-dependent cellular cytotoxic responses to infective and tissue-dwelling O. volvulus larvae. Strengthened monocyte attracting and activation regulated chemokine responses could enhance effector cell migration and activation against larval stages of O.volvulus, possibly also eliciting resistance to further parasite infections. [ABSTRACT FROM AUTHOR]

Parasitic diseases are considered to be one of the most prevalent pathologies worldwide. They are characterized as one of the most critical sanitary problems in cattle, causing a decrease in the productive capacity of parasitized animals, which translates into economic losses. Intestinal parasitism in cattle is caused by protozoa and helminths, and its manifestation is generally multi-etiological. Clinical signs in gastrointestinal parasitism may vary depending on parasite load, parasite species, and host immunity. This research aimed to determine the prevalence of the main parasitic families affecting cattle in the central province of the department of Boyacá. A cross-sectional study with simple random sampling was carried out, where 716 fecal samples were taken and processed using a modified Ritchie technique. An overall prevalence of 95,6% was determined, and the most prevalent families were Trichostrongylidae, Eimeriidae, Taeniidae, and Trichuridae. The age showed no significant statistical association with most of the parasitic families, except for the Strongyloididae family. The breeds showed a correlation with the Trichostrongylidae, Eimeriidae, Strongylidae, Chabertiidae, and Taeniidae families. The results show the high prevalence of GIP (gastrointestinal parasites) in cattle of the central province of the department of Boyacá. [ABSTRACT FROM AUTHOR]

Cryo-electron tomography (cryo-ET) is a cryo-electron microscopy (EM) approach that allows 3D imaging of cellular structures in near-native, frozen-hydrated conditions with molecular resolution. Continued development of technologies, including direct electron detectors, phase plates, and energy filters, has improved the information yield from cellular samples, which is further extended by newly developed workflows for data collection and analyses. Moreover, advanced sample-thinning techniques, such as cryogenic focused ion-beam (cryo-FIB) milling, provide access to parasitic events and structures that were previously inaccessible for cryo-ET. Cryo-ET has therefore become more versatile and capable of transforming our understanding of parasite biology, particularly that of apicomplexans. This review discusses cryo-ET's implementation, its recent contributions, and how it can reveal pathogenesis mechanisms in the near future using apicomplexans as a case study. This review discusses recent advances in cryo-electron tomography (cryo-ET) data collection schemes, imaging technologies, and data processing and analyses such as annotation and subtomogram averaging that have augmented its impact on parasitology. The review illustrates workflows for cryo-ET incorporating additional technologies such as cryogenic focused ion-beam (cryo-FIB) milling that grant cryo-ET access to previously inaccessible biology. The review demonstrates the use of cryogenic correlative light and electron microscopy (cryo-CLEM) and other microscopy techniques to aid in targeted cryo-FIB milling and/or cryo-ET. The review cites studies on apicomplexan biology that demonstrate the current capabilities of cryo-ET. These include cryo-ET structures of apical complex components such as the conoid and the rhoptry secretion system, cytoskeletal elements such as actin and microtubule filaments, and other cellular organelles. [ABSTRACT FROM AUTHOR]

Simple Summary: The elasmobranchs, being at the apex of the marine food chain, act as final receptors of polluting elements that are regularly discharged into the sea and, therefore, usually are considered good bioindicators of environmental pollution. The main goal of this study was to describe helminthic communities, hematological parameters, and the concentrations of trace elements in vertebrae, skin, and liver for a population of lesser spotted dogfish from the Tyrrhenian Sea. Findings suggest that there is sometimes a correlation among these parameters and between them as well as environmental pollution. Parasitological, hematological, and ecotoxicological analyses were carried out on a population of lesser spotted dogfish Scyliorhinus canicula from the central Mediterranean Sea. Parasitological analyses highlighted a poor helminthic community, highly dominated by a single taxon represented by the cestode Nybelinia sp. No differences in the parasitic load between females and males were observed. Hematological analyses showed that the number of leukocytes was significantly lower in the sharks that resulted in parasitism, and this could be due to the ability of some trace elements, such as arsenic, weakening the immune system and exposing animals to a higher risk of parasite infection, although further hematological and parasitological analyses are required on a larger number of samples. Trace elements analyses in the vertebrae, skin, and liver highlighted that the most abundant and potentially toxic elements were lead (Pb), arsenic (As), and cadmium (Cd). Other trace elements were also abundant, such as manganese (Mn), zinc (Zn), nickel (Ni), copper (Cu), and iron (Fe). Pb, As, and Mn showed the highest concentrations in vertebrae, while Cd, Cu, and Zn were the highest in the liver, probably due to their concentration in the prey items of the sharks; Fe and Ni showed the highest concentrations in the skin, due to their presence in the water column, especially along the coast where animals were collected. The concentration of some trace elements analyzed in the vertebrae decreased with the growth of the sharks. These results confirm that elasmobranchs, being predators at the apex of the marine food chain, act as final receptors for a series of polluting elements regularly discharged into the sea. [ABSTRACT FROM AUTHOR]

Original data on diet, internal anatomy, morphology, reproduction, and parasites of Chiroderma doriae vizottoi from the State of Ceará (Brazil) are presented. Intact and crushed seeds of Solanum rhytidoandrum and scales of Lepidoptera were detected in the gastrointestinal tract and feces. Observation of internal organs did not reveal any abnormalities; the intestines were, on average, 11 times longer than the animal's body length. Reproduction seems to occur in the rainy season. The association with an ectoparasite, Mastoptera sp. (Diptera, Streblidae), was recorded. [ABSTRACT FROM AUTHOR]

Background: Echinococcosis is a common parasite with zoonotic character created by a small cestode, Echinococcus spp., and is an important public health problem in Turkey as well as all over the world. We aimed to investigate antibodies in serum samples of suspected Echinococcosis patients sent to the National Parasitology Reference Laboratories of the General Directorate of Public Health. Methods: Serum samples of 2390 patients sent to our laboratory between January 1, 2014 and May 01, 2019, evaluated by ELISA, Indirect Hemagglutination Test (IHA) and Western Blot (WB) methods are presented. Our laboratory is the national reference laboratory. All kinds of tests requested from suspected patients can be performed Results: Overall, 1199 (50.2%) of 2390 serum samples were female and 1191 (49.8%) were male. It was observed that 178 (14.9%) of men and 210 (17.5%) of women were seropositive. There was no statistical difference between the sexes in terms of seropositivity. Of all samples, 1941 (81.2%) were negative, 388 (16.2%) were positive, and 61 (2.6%) were borderline. Results determined as borderline are considered suspicious and a recommendation is made to repeat the test after 15 days. A statistical difference was found in the distribution of seropositivity by years. While seropositivity was lowest in 2014, it was found to be highest in 2018 and 2019. Conclusion: Despite all the precautions taken, it is seen that echinococcosis still continues to exist in Turkey as a zoonotic disease. Hence, CE has been involved in Turkey Zoonotic Diseases Action Plan (2019-2023) and decided to carry out studies for the protection and prevention of the disease. [ABSTRACT FROM AUTHOR]

Beef is a source of vitamins and nutrients for humans and in Brazil, there is a large production and demand for this product. From this, the objective of this work was to evaluate the quality of fresh beef, whole and ground, sold in the main butchers in the municipality of Castanhal - PA. Physicochemical analyses such as pH, Eber test for ammonia and hydrogen sulfide, filtration test, cooking test, and detection of sodium sulfite were performed. Forty-eight samples of meat, of 250 g each, were collected on alternate days, corresponding to 24 samples of whole cut and 24 samples of ground meat, performed in 3 repetitions. All samples were negative; 81.25% were positive for hydrogen sulfide; in the cooking test, 87.5% presented normal meat conditions and 12.5% presented suspect conditions; in infiltration, 39.58% of the samples were in medium conservation conditions and 60.41% were in suspect meat conditions; in the detection of sodium sulfite, 100% of the samples tested negative. In the pH results, the mean values ranged from 5.67-6.3 in the whole samples and 5.61-6.67 in the ground samples, showing a significant difference at the 5% significance level, in samples one, whole, and ground, by ANO-VA and Tukey's test. Based on the results found, it was observed that the quality of fresh beef is not marketed properly in the city's establishments, requiring more attention from inspection agencies and the consumer. [ABSTRACT FROM AUTHOR]

Background: Rapid diagnostic tests (RDTs) are widely used for malaria diagnosis of both symptomatic and asymptomatic infections. Although RDTs are a reliable and practical diagnostic tool, the sensitivity of histidine-rich protein 2 (HRP2)-based RDTs can be reduced if pfhrp2 or pfhrp3 (pfhrp2/3) gene deletions exist in the Plasmodium falciparum parasite population. This study evaluated dried blood spot (DBS) samples collected from a national household survey to investigate the presence of pfhrp2/3 deletions and the performance of the RDT used in the cross-sectional survey in a low transmission setting. Methods: The 2015 Ethiopia Malaria Indicator Survey tested household members by RDT and collected DBS samples. DBS (n = 2648) from three regions in northern Ethiopia were tested by multiplex bead-based antigen detection assay after completion of the survey. The multiplex assay detected pan-Plasmodium lactate dehydrogenase (LDH), pAldolase, and HRP2 antigens in samples. Samples suspected for pfhrp2/3 gene deletions (pLDH and/or pAldolase positive but low or absent HRP2) were further investigated by molecular assays for gene deletions. Antigen results were also compared to each individual's RDT results. Dose–response logistic regression models were fit to estimate RDT level of detection (LOD) antigen concentrations at which 50, 75, 90, and 95% of the RDTs returned a positive result during this survey. Results: Out of 2,648 samples assayed, 29 were positive for pLDH or pAldolase antigens but low or absent for HRP2 signal, and 15 of these samples (51.7%) were successfully genotyped for pfhrp2/3. Of these 15 P. falciparum infections, eight showed single deletions in pfhrp3, one showed a single pfhrp2 deletion, and six were pfhrp2/3 double-deletions. Six pfhrp2 deletions were observed in Tigray and one in Amhara. Twenty-five were positive for HRP2 by the survey RDT while the more sensitive bead assay detected 30 HRP2-positive samples. A lower concentration of HRP2 antigen generated a positive test result by RDT compared to pLDH (95% LOD: 16.9 ng/mL vs. 319.2 ng/mL, respectively). Conclusions: There is evidence of dual pfhrp2/3 gene deletions in the Tigray and Amhara regions of Ethiopia in 2015. As the prevalence of malaria was very low (< 2%), it is difficult to make strong conclusions on RDT performance, but these results challenge the utility of biomarkers in household surveys in very low transmission settings. [ABSTRACT FROM AUTHOR]

Myiasis is a disease that occurs when adult forms of some diptera species are non-parasitic, while larval forms (Diptera: Calliphoridae, Muscidae and Sarcophagidae) feed on necrotic, living, or dead tissues of humans and vertebrates or fluids from body tissues or ingested food. Myiasis causes serious economic losses and health problems in humans and animals, especially in rural areas of tropical and subtropical countries where cattle, sheep and goat breeding are common. The case of myiasis is classified in many ways according to the parasite-host relationships or the tissues and organs in which the diptera larvae located: external myiasis if it settles on the skin surface of the hosts; internal myiasis if it settles in organs or body cavities. Diptera larvae collected from the preputium of a sacrificial goat were brought to the parasitology laboratory in 70% ethanol for identification. According to the microscopic examination, third instar larvae of Wohlfahrtia magnifica (Diptera: Sarcophagidae) were detected in samples. The aim of this study was to present the cases of external and internal myiasis in Turkey, together with the first case of preputial myiasis of goat caused by W. magnifica in Turkey. [ABSTRACT FROM AUTHOR]

The difficulty of faithfully recapitulating malarial protein complexes in heterologous expression systems has long impeded structural study for much of the Plasmodium falciparum proteome. However, recent advances in single-particle cryo electron microscopy (cryoEM) now enable structure determination at atomic resolution with significantly reduced requirements for both sample quantity and purity. Combined with recent developments in gene editing, these advances open the door to structure determination and structural proteomics of macromolecular complexes enriched directly from P. falciparum parasites. Furthermore, the combination of cryoEM with the rapidly emerging use of in situ cryo electron tomography (cryoET) to directly visualize ultrastructures and protein complexes in the native cellular context will yield exciting new insights into the molecular machinery underpinning malaria parasite biology and pathogenesis. With half the world's population currently at risk, malaria remains a significant global health burden. The difficulty of expressing many malarial protein complexes in heterologous systems has precluded structural and biochemical studies, impeding efforts to elucidate the functions and molecular mechanisms of many important but poorly understood biological pathways, including potential therapeutic targets. Recent and ongoing advances in structure determination of macromolecular complexes using cryo electron microscopy (cryoEM) provide new avenues for structural study of the P. falciparum proteome, much of which previously resisted structure determination. CryoEM of endogenously derived macromolecular complexes, enabled by the significantly reduced sample requirements of cryoEM studies, will lead to the discovery of so far unknown native substrates, binding partners, and modifications. [ABSTRACT FROM AUTHOR]

The concept of a 'Golden Age' of parasitology over the period 1875–1925 has been promoted. This is challenged on scientific grounds, the influence of colonialism, and the absence of informed consent for test-subjects. An alternative inclusive view of history is proposed based on themes of scientific, technological, and sociological advancement. [ABSTRACT FROM AUTHOR]

During migrations, birds are exposed to a wide variety of parasites. It has been suggested that shorebird migration and other movements play a critical role in structuring their parasite communities. The objective of this study was to characterize the helminth communities of two sympatric Nearctic migratory shorebird species in their non-breeding grounds in Argentine Patagonia and to assess what factors influence their structuring. The migration of these two bird species span from pole to pole as they breed in the Canadian Arctic and winter at southernmost South America. In contrast to the Arctic, the helminth communities of these birds have never been studied at their austral non-breeding sites. A total of 44 Calidris bairdii and 50 Calidris fuscicollis collected at various coastal marine and inland sites were analyzed for helminths. Ecological parameters were calculated at component community (host population) and infracommunity (single individual hosts) levels. A total of 26 helminth taxa were found, included in 14 families and 20 genera. Results showed that parasite richness and total prevalence were higher in C. bairdii than in C. fuscicollis. Richness, diversity, dominance and abundance values in the infracommunities were generally low, being lower in C. fuscicollis. The infracommunities were characterized by being heterogeneous, unstructured and unpredictable. Possible causes of this pattern are discussed. It is clear that multiple factors influence parasitic diversity; however, considering our observations, we think that habitat use is possibly the main structuring factor of the helminth communities of these two shorebird species. [ABSTRACT FROM AUTHOR]

Background: Neurological signs, such as head tilt, torticollis, paralysis, and seizures, are common in rabbits. Differential diagnoses include two zoonotic infections caused by the microsporidial fungi Encephalitozoon cuniculi and the apicomplexan protozoa Toxoplasma gondii. Both infections are mainly latent in rabbits but may cause severe or even fatal disease. Although several international studies have reported the seroprevalence of these pathogens in different commercial rabbit populations, similar prevalence studies and risk-factor analyses among family-owned pet rabbits are uncommon and lacking in Scandinavia. We sought to estimate the seroprevalence and possible risk factors for E. cuniculi and T. gondii among Finnish pet rabbits. We used ELISA to measure E. cuniculi IgG seroprevalence of 247 rabbits and modified direct agglutination test for T. gondii seroprevalence of 270 rabbits. Samples were collected as part of the Finnish Pet Rabbit Health Research project. Internet-based questionnaires (n = 231) completed by the rabbit owners were used for risk-factor analysis. Results: The apparent seroprevalence of E. cuniculi was 29.2% and true seroprevalence of T. gondii 3.9%. Risk factors were analysed only for E. cuniculi due to the low T. gondii seroprevalence. The final multivariable logistic regression model revealed that rabbits spending the whole summer outdoors had a higher risk of being E. cuniculi seropositive than rabbits with limited outdoor access. Additionally, rabbits living in households with only one or two rabbits had higher risk of being E. cuniculi seropositive than those in multi-rabbit households. Conclusions: Nearly one third of Finnish pet rabbits participating in this study had E. cuniculi IgG antibodies, indicating previous exposure to this pathogen. The prevalence is similar to that reported previously in clinically healthy rabbit populations in UK and Korea. While the seroprevalence of T. gondii was low (3.9%), antibodies were detected. Therefore, these zoonotic parasitic infections should be considered as differential diagnoses when treating rabbits. [ABSTRACT FROM AUTHOR]

Gastrointestinal parasites are frequently found in domestic animals, with important role in animal and public health. Among gastrointestinal parasites of dogs and cats Toxocara spp. and Ancylostoma spp. are reported as the most common parasites found in dogs and cats in the world caunsing digestive damage, including death, and with great importance in public health causing visceral larva migrans and cutaneous larva migrans respectively. This study aimed verify the occurrence of gastroenteric parasites in dogs and cats from Mineiros, Goiás, in association with epidemiological aspects. In total, 103 fecal samples (93 from dogs and 10 from cats) from April 2017 to July 2018 were collected by spontaneous defecation and processed for search of eggs and oocysts by the Willis (adapted) technique. Toxocara spp. was the most frequent parasite identified in dogs, with 34.41% frequency (32/93 samples), followed by Ancylostoma spp. (11.83%, 11/93 samples) and Cystoisospora spp. (1.07%, 1/93 samples). Fecal samples from cats, showed a similar result, being Toxocara spp. the most frequent parasite (40%, 4/10 samples), followed by Ancylostoma spp. (20%, 2/10 samples) and Cystoisospora spp. (20%, 2/10 samples). Young animals were 10% more positive for parasites comparing to elderly and adult animals (odds ratio=1.1), as well as animals with access outdoors 20% more parasitized (odds ratio=1.2). The study showed the most common gastrintesinal parasites of dogs and acts from Mineiros, Goiás. [ABSTRACT FROM AUTHOR]

Entomopathogenic nematodes (EPNs), including Heterorhabditis and Steinernema, are parasitic to insects and contain mutualistically symbiotic bacteria in their intestines (Photorhabdus and Xenorhabdus, respectively) and therefore offer opportunities to study both mutualistic and parasitic symbiosis. The establishment of genetic tools in EPNs has been impeded by limited genetic tractability, inconsistent growth in vitro, variable cryopreservation, and low mating efficiency. We obtained the recently described Steinernema hermaphroditum strain CS34 and optimized its in vitro growth, with a rapid generation time on a lawn of its native symbiotic bacteria Xenorhabdus griffiniae. We developed a simple and efficient cryopreservation method. Previously, S. hermaphroditum isolated from insect hosts was described as producing hermaphrodites in the first generation. We discovered that CS34, when grown in vitro, produced consecutive generations of autonomously reproducing hermaphrodites accompanied by rare males. We performed mutagenesis screens in S. hermaphroditum that produced mutant lines with visible and heritable phenotypes. Genetic analysis of the mutants demonstrated that this species reproduces by self-fertilization rather than parthenogenesis and that its sex is determined chromosomally. Genetic mapping has thus far identified markers on the X chromosome and three of four autosomes. We report that S. hermaphroditum CS34 is the first consistently hermaphroditic EPN and is suitable for genetic model development to study naturally occurring mutualistic symbiosis and insect parasitism. [ABSTRACT FROM AUTHOR]

Strongyloides stercoralis is a soil‐transmitted nematode that is estimated to infect millions of people per year worldwide. However, cases are less commonly seen in the United States. This report highlights the importance of when to include Strongyloides stercoralis in the differential diagnosis of patients presenting eosinophilia within the United States. [ABSTRACT FROM AUTHOR]

The article presents the discussion on reflecting on the progress made in parasitological research in Nigeria. Topics include Malaria, onchocerciasis, lymphatic filariasis, schistosomiasis, and soil-transmitted helminthiasis are among the most prevalent parasitic diseases in the country; and researchers, healthcare professionals, donor agencies and policymakers to address these challenges, by the establishment of control and elimination programmes.

Schistosomiasis is a parasitic infection caused by Schistosoma japonicum. It remains a principal local health issue in the Philippines, demonstrating endemicity in 28 provinces and afflicting thousands of Filipino individuals annually. Despite this, no clear distribution maps for the disease have been comprehensively reported. Therefore, species distribution modeling (SDM) employing the MaxEnt algorithm and GIS application techniques was utilized to denote the potential risk of schistosomiasis in the country. With a high AUC score of 0.846, the SDM yielded a favorable and reliable correlative map illustrating a predicted schistosomal temporal distribution concentrated primarily on the country's eastern portion with a more pronounced wet than dry season. The precipitation of the driest quarter was determined to be the most significant contributing factor among the bioclimatic variables evaluated. This suggests a possible increase in adaptations concerning the rainfall and thermal tolerances of the parasites' vectors. Moreover, socioeconomic status between Philippine regions revealed an inverse proportion with the number of schistosomiasis cases. This study also discussed the potential role of climate change on the range shifts and the potential risk of parasite infection in the Philippines. [Display omitted] • High-risk areas of schistosomiasis were predicted in the eastern Philippines. • Precipitation of the driest quarter is the most influential bioclimatic predictor. • GIS application can be used for policy creation of mitigating schistosomiasis. • Model reveals areas with the same condition for recorded schistosome occurrence. [ABSTRACT FROM AUTHOR]

Antecedentes: los Opisthorchiidae son una familia de parásitos trematodos‚ que infectan principalmente a vertebrados‚ incluidos humanos‚ y se encuentran en diferentes partes del mundo‚ especialmente en regiones donde se consumen pescados crudos o poco cocidos. En Colombia ha sido comprobada la presencia de Opisthorchiidos asociados a animales domésticos y humanos sin establecerse rutas de atención o investigación‚ demostrando que su impacto está subvalorado. Objetivo: detección y caracterización molecular y taxonómica de Opisthorchiidos asociados a cultivos piscícolas de economía campesina en el Urabá antioqueño Métodos: se evaluaron diez cultivos piscícolas de economía campesina con presencia de animales domésticos y sus afluentes. De cada cultivo se tomaron 20 peces y muestras de coprológicos de los animales domésticos. Se hizo una evaluación preliminar de ojos y aletas bajo estereoscopio y luego se utilizó un protocolo para digestión peptídica de la musculatura de los peces‚ para la búsqueda de morfos usando microscopio óptico. Las muestras fueron enviadas en alcohol al laboratorio para extracción de DNA. Se realizó PCR con siente pares de cebadores. Proyecto aprobado en acta N°131 por Comité de Ética para la Experimentación Animal de la UdeA. Resultados: se analizaron un total de 321 peces pertenecientes en su mayoría a las especies de Oreochromis niloticus (tilapia) (200/321)‚ otras (Poecilia reticulata y Colossoma macropomum)‚ 14 coprológicos‚ todos negativos. En total se han encontrado doce metacercarias de Diplostomidae‚ Echinostomatidae‚ Microphallidae y Clinostomum y Acanthocephalo peces de las especies P. reticulata y O. niloticus. Se logró estandarizar y optimizar la PCR para los siete pares de cebadores. Conclusiones: hasta el momento se ha logrado estandarizar y optimizar las PCRs para la detención de Opisthorchiidos así como comprobar su presencia en la región del Urabá. Se espera que los hallazgos de estos parásitos asociados a animales domésticos e incluso a humanos permitirá comunicar a las comunidades y los sistemas de salud médico y veterinario sobre su presencia e importancia‚ contribuyendo al aviso de alertas tempranas y riesgos en la zona de estudio. [ABSTRACT FROM AUTHOR]

[Display omitted] • How a background in diagnostic cattle babesiosis led to the argument that excess TNF is the key to pathogenesis. • The author summarises also following TNF into innate immunity, neurophysiology and neurodegenerative diseases. • These advances in physiology and pathophysiology are still growing rapidly, leading to wide adoption of useful treatments. • Many of these steps can be illustrated and expanded upon in parasitic diseases. • This involvement in neurodegenerative disease is being highly illuminating about human nature and scruples in science. This is an account of how it can prove possible to carve a reasonable scientific career by following what brought most scientific thrill rather than pursue a safe, institution-directed, path. The fascination began when I noticed, quite unexpectedly, that the normal mouse immune response causes Babesia microti to die, en masse, inside circulating red cells. It eventuated that prior Bacillus Calmette Guerin infection caused the same outcome, even before the protozoal infection became patent. It also rendered mice quite immune, long term. I acquired an obsession about this telling us how little we know. Surrounded by basic immunologists, parasitologists and virologists in London, I had been given, in the days that funding was ample, the opportunity to follow any promising lead with a free hand. Through Bacillus Calmette Guerin, this meant stumbling through a set of phenomena that were in their infancies, and could be explained only through nebulous novel soluble mediators such as TNF, described the following year as causing the in vivo necrosis of tumours in mice. Beginning with malarial disease pathogenesis, I followed TNF wherever it led, into innate immunity, acute and chronic infections, neurophysiology and neurodegenerative diseases, in all of which states awareness of the role of this cytokine is still growing fast. Many of these steps can be illustrated and expanded upon in parasitic diseases. Covering the importance of TNF in the pathogenesis of neurodegenerative disease has proved to be highly illuminating, scientifically and otherwise. But the insights it has given me into understanding the temptations to which patent-owners can succumb when faced with opportunities to put money before people is not for the faint hearted. Clearly, parasitologists inhabit a much more common-good yet science-orientated, civilised, world. [ABSTRACT FROM AUTHOR]

[Display omitted] • The article presents a history of research on parasite ecology over the past 50 years. • Twelve key advances are highlighted, each one having shaped the course of research. • Seminal contributions are identified, as well as influential research trends. • A quantitative summary of ecological research published in the International Journal for Parasitology is also presented. • Some opportunities and challenges facing ecological parasitology are discussed. In the five decades since the first publication of the International Journal for Parasitology, ecological parasitology has grown from modest beginnings to become a modern discipline with a strong theoretical foundation, a diverse toolkit, and a multidisciplinary approach. In this review, I highlight 12 advances in the field that have spurred its growth over the past 50 years. Where relevant, I identify pivotal contributions that have altered the course of research, as well as the influence of developments in other fields such as mainstream ecology and molecular biology. The 12 key advances discussed are in areas including parasite population dynamics and community assembly, the regulation of host population abundance and food web structure, parasites as agents of natural selection, the impacts of biodiversity and anthropogenic changes on host-parasite interactions, the biogeography of parasite diversity, and the evolutionary genetics of parasites. I conclude by identifying some challenges and opportunities lying ahead, which need to be met for the future growth of ecological research on host-parasite interactions. [ABSTRACT FROM AUTHOR]

Entamoeba gingivalis has been associated with periodontal diseases. Baseline data from the background population, which could help delimit the role of the parasite in health and disease, remain limited. To describe epidemiological features, genetic diversity, and associations with oral microbiome signatures of E. gingivalis colonisation in Tanzanians with non-oral/non-dental diseases. DNAs from 92 oral washings from 52 participants were subject to metabarcoding of ribosomal genes. DNA sequences were identified to genus level and submitted to oral microbiota diversity analyses. Sixteen (31%) of the 52 study participants were E. gingivalis-positive, with no difference in positivity rate according to gender or age. Only one subtype (ST1) was found. Individuals testing positive for E. gingivalis had higher oral microbiota alpha diversity than those testing negative (P = 0.03). Eight of the top-ten most common bacterial genera were shared between the two groups (Alloprevotella, Fusobacterium, Gemella, Haemophilus, Neisseria, Porphyromonas, Prevotella, Streptococcus, and Veillonella). Meanwhile, E. gingivalis carriers and non-carriers were more likely to have Aggregatibacter and Rothia, respectively, among the top-ten most common genera. About one third of the cohort carried E. gingivalis ST1, and carriers had higher oral microbiome diversity and were more predominantly colonized by Aggregatibacter. [ABSTRACT FROM AUTHOR]

Cutaneous leishmaniasis (CL) is caused by Leishmania donovani in Sri Lanka. Pentavalent antimonials (e.g., sodium stibogluconate [SSG]) remain first-line drugs for CL with no new effective treatments emerging. We studied whole blood and lesion transcriptomes from Sri Lankan patients with CL at presentation and during SSG treatment. From lesions but not whole blood, we identified differential expression of immune-related genes, including immune checkpoint molecules, after onset of treatment. Using spatial profiling and RNA-FISH, we confirmed reduced expression of programmed death-ligand 1 (PD-L1) and indoleamine 2,3-dioxygenase 1 (IDO1) proteins on treatment in lesions of a second validation cohort and further demonstrated significantly higher expression of these checkpoint molecules on parasite-infected compared with noninfected lesional CD68+ monocytes and macrophages. Crucially, early reduction in PD-L1 but not IDO1 expression was predictive of rate of clinical cure (HR = 4.88) and occurred in parallel with reduction in parasite load. Our data support a model whereby the initial anti-leishmanial activity of antimonial drugs alleviates checkpoint inhibition on T cells, facilitating immune-drug synergism and clinical cure. Our findings demonstrate that PD-L1 expression can be used as a predictor of rapidity of clinical response to SSG treatment in Sri Lanka and support further evaluation of PD-L1 as a host-directed therapeutic in leishmaniasis. [ABSTRACT FROM AUTHOR]

The classification of "parasites" in the medical field is a challenging notion, a group which historically has included all eukaryotes exclusive of fungi that invade and derive resources from the human host. Since antiquity, humans have been identifying and documenting parasitic infections, and this collective catalog of parasitic agents has expanded considerably with technology. As our understanding of species boundaries and the use of molecular tools has evolved, so has our concept of the taxonomy of human parasites. Consequently, new species have been recognized while others have been relegated to synonyms. On the other hand, the decline of expertise in classical parasitology and limited curricula have led to a loss of awareness of many rarely encountered species. Here, we provide a comprehensive checklist of all reported eukaryotic organisms (excluding fungi and allied taxa) parasitizing humans resulting in 274 genus-group taxa and 848 species-group taxa. For each species, or genus where indicated, a concise summary of geographic distribution, natural hosts, route of transmission and site within human host, and vectored pathogens are presented. Ubiquitous, human-adapted species as well as very rare, incidental zoonotic organisms are discussed in this annotated checklist. We also provide a list of 79 excluded genera and species that have been previously reported as human parasites but are not believed to be true human parasites or represent misidentifications or taxonomic changes. [ABSTRACT FROM AUTHOR]

Background Entamoeba histolytica infection is a sexually transmitted disease in some developed countries. Asymptomatic infection often occurs and can be a source of transmission; however, limited data are available regarding the pathogenesis of E. histolytica. Methods This was a single-center, cross-sectional study. Specimens were prospectively collected from patients with clinically suspected cases. Entamoeba histolytica infection was defined as a case in which the identification of E. histolytica was confirmed by polymerase chain reaction (PCR) of a clinical specimen. Data from asymptomatic cases were compared with those from symptomatic invasive cases. Results Sixty-four E. histolytica –infected cases, including 13 asymptomatic cases, were identified during the study period. Microbiological diagnosis was made by endoscopic sampling in 26.6% of these cases (17/64). Endoscopy identified macroscopically visible lesions in all cases; however, the sensitivity of histopathology on biopsy samples was low (45.5%) compared with PCR (94.7%). In asymptomatic cases, infection sites were limited around the proximal colon; moreover, trophozoites were frequently identified at infection sites whereas cystic forms were commonly detected in stools. Gut microbiome analyses showed more uniform composition in asymptomatic cases than in symptomatic invasive cases, which were represented by a relatively high abundance of Ruminococcaceae, Coriobacteriaceae, and Clostridiaceae, and a low abundance of Streptococcaceae. Conclusions These results indicate that the encystation and attenuation of E. histolytica are highly affected by the intestinal contents, including the gut microbiome. [ABSTRACT FROM AUTHOR]