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Toxoplasmosis is a zoonotic parasitic disease of global importance. It is widespread and endemic practically all over the world, with infection prevalence varying by geographic location. The parasite and the disease are neglected, which is illustrated by the lack of baseline information on the prevalence from many regions. Developed, peaceful regions are in better situation to address toxoplasmosis, while the neglected status is particularly pronounced in regions with other challenges. Due to the lack of baseline data, these regions are rarely mentioned in discussions about the neglected status of the disease. A dramatic manifestation of toxoplasmosis, congenital toxoplasmosis, is the dreaded outcome of vertical transmission of the infection from the mother to the unborn child. For this reason, pregnant women are a key target group for primary prevention of T. gondii infections, and baseline data on the prevalence in pregnant women is important. In this cross-sectional seroepidemiological study, we estimated Toxoplasma gondii seroprevalence and evaluated possible risk factors for seropositivity in pregnant women in Kabul, Afghanistan. Altogether 207 of the 431 women included in the study tested positive for immunoglobulin G antibodies against T. gondii, yielding an apparent seroprevalence estimate of 48.03% (95% CI 43.33-52.75). Based on the final multivariable model for T. gondii seropositivity, non-concrete floor in the house and well or river as water source were identified as risk factors for seropositivity, while residence in rural area was a protective factor. The majority of the participants (72.9%) reported that they did not know about T. gondii. Our study is the first to report an estimate of T. gondii seroprevalence in pregnant women in Afghanistan. The high seroprevalence indicates substantial infection pressure, and the results of the risk factor analysis suggest that the environmental route, infection from oocysts, might be the most relevant to address to prevent the infections in the region. Our results contribute to the global discussion on neglected status of toxoplasmosis., Competing Interests: The authors have declared that no competing interests exist.

Practising veterinary medicine has an inherent risk of exposure to zoonotic agents, including the protozoan parasite Toxoplasma gondii. We screened sera of veterinarians authorized to work in Finland for the presence of specific immunoglobulin G antibodies against T. gondii with an enzyme-linked fluorescent assay, and evaluated potential risk factors for T. gondii seropositivity from extensive questionnaire data with almost 1,300 quantitative variables. We used a causal diagram approach to address the complexity of the life cycle of the parasite and its numerous possible transmission routes, and built a multivariable binomial logistic regression model to identify risk factors that are particularly relevant for veterinarians. The samples and questionnaire data were collected in 2009. Altogether, 294 veterinarians, almost 15% of the Finnish veterinary profession, were included in the study. The median age was 39 years, and the majority, 86%, were women. Altogether, 43 (14.6%; 95% confidence interval: 10.9-19.0) of the 294 veterinarians tested seropositive for T. gondii. According to the final model, veterinarians who were at least 40 years old had 2.4 times higher odds to be seropositive than younger veterinarians; veterinarians who lived in the countryside had 4.0 times higher odds to be seropositive than veterinarians who lived in towns; female veterinarians who tasted beef during cooking had 2.6 times higher odds to be seropositive than male veterinarians who did not taste beef during cooking; and veterinarians who did not do small animal practice had 2.3 times higher odds to be seropositive than those who did. The results illustrate the numerous transmission routes of T. gondii., (© 2018 Blackwell Verlag GmbH.)

Toxoplasma gondii is a zoonotic parasite causing high disease burden worldwide. A One Health approach is needed to understand, prevent, and control toxoplasmosis, while knowledge gaps in the One Health aspects have been identified among medical professionals in earlier studies. As a One Health collaboration between veterinary and medical fields, we surveyed the knowledge on toxoplasmosis among medical doctors in Nigeria. The knowledge questions, which the participants answered without consulting literature and colleagues, covered epidemiological One Health aspects as well as clinical interspecialty aspects of T. gondii infections. Altogether 522 medical doctors from four tertiary hospitals completed the questionnaire. The mean number of correct answers in the knowledge questions was 7.5, and 8.4% of the participants selected at least 12 of the 17 correct answers. The proportion of medical doctors scoring such a high score was significantly higher among those who reported having seen a case of clinical toxoplasmosis than in those who did not. While 62% of the medical doctors participating in our study knew that cats can shed T. gondii in their feces, 36% incorrectly suggested that humans could do that too. That T. gondii infection can be meatborne was known by 69%, but that it can be also waterborne only by 28% of the medical doctors participating in our study. Most of the medical doctors, 78%, knew that clinical toxoplasmosis may involve the central nervous system, while only 37% answered that it can involve the eyes. Our results suggested knowledge gaps, which need to be addressed in Continuous Medical Education. The identified gaps included both intersectoral One Health aspects and interspecialty aspects: For prevention and management of toxoplasmosis, knowing the main transmission routes and that the parasite can affect several organs is relevant.

Toxoplasma gondii is an important zoonotic parasite worldwide, but it has received limited attention in Ukraine. A seroepidemiological study was conducted and samples from 452 wild boars that had been hunted in 2006-2011 in 23 of the 25 regions of Ukraine were tested to estimate T. gondii seroprevalence. A locally available commercial enzyme-linked immunosorbent assay (ELISA) was used for the investigation. Additionally, we tested 92 of the sera using a widely used commercial multi-species ELISA and an indirect immunofluorescence antibody test (IFAT). With the locally available ELISA, 35 of the 452 wild boars tested positive, yielding a seroprevalence estimate of 7.7% (95% confidence interval 5.5-10.5). The seropositive wild boars originated from eight of the regions. Using the majority criteria, 10/92 samples tested using both ELISAs and the IFAT were considered positive, yielding an estimated seroprevalence of 10.9% within the subset of samples. The highest seroprevalence was observed in wild boars hunted in Luhansk (30.0%), Odesa (17.7%) and Kharkiv (12.7%). Seroprevalence was higher in older animals (13.3% for age group >12 months and 7.7% for age group ≤12 months). This is the first seroepidemiological study of T. gondii in wild boars in Ukraine. Assuming that seropositivity indicates presence of infectious parasites in the tissues, eating undercooked meat of wild boars hunted in Ukraine could be a potential source of infection to other hosts, including humans.

Toxoplasma gondii is a zoonotic parasite of importance to both human and animal health. The parasite has various transmission routes, and the meat of infected animals appears to be a major source of human infections in Europe. We aimed to estimate T. gondii prevalence in a selection of animal host species. A systematic literature review resulting in 226 eligible publications was carried out, and serological data were analyzed using an age-dependent Bayesian hierarchical model to obtain estimates for the regional T. gondii seroprevalence in livestock, wildlife, and felids. Prevalence estimates varied between species, regions, indoor/outdoor rearing, and types of detection methods applied. The lowest estimated seroprevalence was observed for indoor-kept lagomorphs at 4.8% (95% CI: 1.8–7.5%) and the highest for outdoor-kept sheep at 63.3% (95% CI: 53.0–79.3%). Overall, T. gondii seroprevalence estimates were highest within Eastern Europe, whilst being lowest in Northern Europe. Prevalence data based on direct detection methods were scarce and were not modelled but rather directly summarized by species. The outcomes of the meta-analysis can be used to extrapolate data to areas with a lack of data and provide valuable inputs for future source attribution approaches aiming to estimate the relative contribution of different sources of T. gondii human infection. [ABSTRACT FROM AUTHOR]

Background: Toxoplasma gondii is a widespread occurring parasite infecting warm-blooded animals, including pigs and humans. The aims of this study were to estimate the prevalence of anti-T. gondii antibodies and to evaluate risk factors for T. gondii seropositivity in breeding pigs raised in Estonia. Sera from 382 pigs were tested with a commercial direct agglutination test, using a cut-off titer of 40 for seropositivity, for the presence of anti-T. gondii immunoglobulin G antibodies. Results: Twenty-two (5.8%) of the 382 pigs tested seropositive for T. gondii, and 6 of the 14 herds had at least one seropositive pig. The proportion of seropositive pigs within the herds ranged between 0 and 43%. Gender appeared as a significant factor, with sows having 5.6 times higher odds to be seropositive to T. gondii than boars. Seroprevalence did not increase with age. Conclusions: Anti-T. gondii antibodies were present in a substantial proportion of breeding pig herds in Estonia. On the other hand, the presence of herds without seropositive pigs illustrates that porcine T. gondii infections can be avoided even in a country where the parasite is endemic and common in several other host species. [ABSTRACT FROM AUTHOR]

Toxoplasma gondii is a protozoan parasite with both public health and veterinary importance. The aims of our study were to estimate the T. gondii seroprevalence in sheep in Latvia and to evaluate potential risk factors for seropositivity. The blood samples investigated were collected from 1039 sheep from 84 farms between January 2012 and April 2013. The sera were tested for immunoglobulin G antibodies against T. gondii using an in-house enzyme-linked immunosorbent assay. Antibodies against T. gondii were detected in 179 (17.2%) of the sheep, and at least one seropositive sheep was found on 37 (44.0%) of the farms. The seroprevalence was significantly higher in adult (over 1 year old) sheep than in juveniles-the adult sheep had 1.8 times higher odds to test seropositive than did the juveniles. The seroprevalence was significantly higher in Latvian Dark Headed sheep than in crossbreed and German Merino sheep. Sheep from large herds (with more than 100 sheep), as well as those from farms with cattle, had higher odds to test seropositive, whereas the presence of poultry on the farm appeared as a protecting factor. The results show that sheep in Latvia are commonly exposed to T. gondii. [ABSTRACT FROM AUTHOR]

Background: Congenital toxoplasmosis (CT) causes a substantial disease burden worldwide. The aim of this study was to estimate the disease burden of CT in Denmark, a developed country with free public healthcare and nationwide data available. Methods: Using data primarily from two public health surveillance programmes conducted between 1992 and 2007, we estimated the incidence, occurrence of sequelae, mortality and the burden of disease in terms of disability-adjusted life years (DALYs) of CT in Denmark in 2014. Findings: We estimated that 14 children were born with CT in 2014, of which six will have developed sequelae by the age of 12. CT resulted in a total disease burden of 123 DALYs (95% uncertainty interval [UI], 100–148), of which 78 (95% UI, 64–94) were due to foetal loss and 2 (95% UI, 1–3) were due to neonatal death; the remaining burden was due to moderate to severe life-long sequelae. A comparison of the estimated incidence of CT with the number of reported CT cases in 2008–2014 indicated that for each reported CT case, at least five other CT cases could be expected to have occurred and gone unreported. Interpretation: Early onset, severity, and life-long duration of sequelae have a major effect on the disease burden of CT. Our data suggest that CT is under-diagnosed or under-reported in Denmark. The estimated disease burden and public health impact in Denmark is lower than in other European countries, highlighting the need for country-specific studies. [ABSTRACT FROM AUTHOR]

Toxoplasma gondii is a zoonotic protozoan parasite that thrives in Estonia. In this nationwide cross-sectional study, we tested sera from 3991 cattle, collected from 228 farms in 2012–2013, for anti- T. gondii immunoglobulin G antibodies using a commercial direct agglutination test. Titer of 100 was set as cut-off: samples that tested positive at the dilution 1:100 were defined as positive. The apparent animal-level seroprevalence was 18.62%. At least one seropositive animal was found on 68.86% of the farms, and seropositive cattle were detected in all counties. The seroprevalence appeared to increase with age until five years (60–71 months) of age, but had no obvious pattern in the older animals. Animals of the local Estonian Red breed had higher odds to test seropositive than did animals of the Estonian Holstein breed. Whether the farm focused on dairy or beef cattle was not associated with an animal testing T. gondii seropositive nor with finding at least one T. gondii seropositive animal on the farm. The odds of finding at least one T. gondii seropositive animal on the farm were higher if the herd size was above median (105 in dairy and mixed dairy farms; 35 in beef and mixed beef farms). The results indicate that T. gondii is endemic within the agricultural setting in Estonia and present on the majority of cattle farms. [ABSTRACT FROM AUTHOR]

Background: Although the prevalence of human Toxoplasma gondii infections is high in Estonia, no information is available on the prevalence of infections in the local animal populations. Wild boars are a good indicator species for estimating the prevalence and spread of T. gondii and were thus investigated in this nationwide cross-sectional study. Volunteer hunters sampled cardiac or skeletal muscle of 471 wild boars legally hunted for human consumption in Estonia during the hunting season of 2012-2013. Serosanguineous meat juice samples were obtained from thawed tissue samples, diluted 1:40, and screened for specific anti-T. gondii IgG antibodies with a commercial direct agglutination test. Results: Almost one-quarter (113; 24%) of the wild boars examined were seropositive for T. gondii. The seroprevalence did not differ significantly between age groups or sexes. The seroprevalence was lowest in Viljandimaa, which is located in the southern part of Estonia. In other counties, the infection was evenly prevalent. Conclusions: In Estonia, wild boars are commonly exposed to T. gondii, which is endemic and widespread. The consumption of raw or undercooked meat of Estonian wild boars may pose an infection risk to humans and other hosts. [ABSTRACT FROM AUTHOR]

The article discusses research which investigated the presence of Toxoplasma gondii infections in Eurasian lynx in Finland. It cites the use of a direct agglutination test in detecting specific antibodies in lynx samples that were legally hunted during the 2010-2011 season. Findings revealed that older lynx had 14.3 times higher odds of being antibody-positive and the lynx from the southwest were more often antibody positive.

The article presents a study which examined the fatal infection in three Eurasian red squirrels Sciurus vulgaris sent for necropsy in Finland between May 2006 and April 2009, from Toxoplasma (T.) gondii parasites belonging to endemic genotype II. The main histopathologic findings were multifocal necrosis in the liver and the spleen, lymphoplasmacytic cellular infiltrations in the liver and lungs, among others. T. gondii parasites were identified in all the tissues available from the squirrels.

The apicomplexan zoonotic parasite Toxoplasma gondii has three infective stages: sporozoites in sporulated oocysts, which are shed in unsporulated form into the environment by infected felids; tissue cysts containing bradyzoites, and fast replicating tachyzoites that are responsible for acute toxoplasmosis. The contribution of oocysts to infections in both humans and animals is understudied despite being highly relevant. Only a few diagnostic antigens have been described to be capable of discriminating which parasite stage has caused an infection. Here we provide an extensive overview of the antigens and serological assays used to detect oocyst-driven infections in humans and animals according to the literature. In addition, we critically discuss the possibility to exploit the increasing knowledge of the T. gondii genome and the various 'omics datasets available, by applying predictive algorithms, for the identification of new oocyst-specific proteins for diagnostic purposes. Finally, we propose a workflow for how such antigens and assays based on them should be evaluated to ensure reproducible and robust results. [ABSTRACT FROM AUTHOR]

Human infection with the important zoonotic foodborne pathogen Toxoplasma gondii has been associated with unwashed raw fresh produce consumption. The lack of a standardised detection method limits the estimation of fresh produce as an infection source. To support method development and standardisation, an extensive literature review and a multi-attribute assessment were performed to analyse the key aspects of published methods for the detection of T. gondii oocyst contamination in fresh produce. Seventy-seven published studies were included, with 14 focusing on fresh produce. Information gathered from expert laboratories via an online questionnaire were also included. Our findings show that procedures for oocyst recovery from fresh produce mostly involved sample washing and pelleting of the washing eluate by centrifugation, although washing procedures and buffers varied. DNA extraction procedures including mechanical or thermal shocks were identified as necessary steps to break the robust oocyst wall. The most suitable DNA detection protocols rely on qPCR, mostly targeting the B1 gene or the 529 bp repetitive element. When reported, validation data for the different detection methods were not comparable and none of the methods were supported by an interlaboratory comparative study. The results of this review will pave the way for an ongoing development of a widely applicable standard operating procedure. [ABSTRACT FROM AUTHOR]