Oral Sex as a Potential Route for Toxoplasma Gondii Transmission: Experiment with Human Semen and Laboratory Mice Model.

PURPOSE: Toxoplasma gondii is one of the most widespread parasites in the human population globally. Several modes of its transmission have been proposed: some are well-researched and confirmed, others remain unconfirmed. One unconfirmed hypothesis pertains to potential transmission of Toxoplasma gondii via oral sex (fellatio) in humans. A recent study found tissue cysts in the semen of men with latent toxoplasmosis. Therefore, we aimed to test the hypothesis of Toxoplasma gondii transmission through oral sex experimentally. METHODS: Eighty-two laboratory mice were orally administered semen samples from 41 men with latent toxoplasmosis. These semen samples were examined for the presence of Toxoplasma gondii DNA using PCR. RESULTS: We detected Toxoplasma gondii DNA in three of the 41 semen samples from men with latent toxoplasmosis. Oral administration of semen samples to laboratory mice did not result in parasite transmission. CONCLUSION: We have not demonstrated the transmission of Toxoplasma to mice by oral exposure to semen from infected men. While this does not conclusively rule out the possibility of such transmission in humans, the results suggest that, if it does occur, this mode of transmission is likely infrequent.

Association between lymphadenopathy after toxoplasmosis seroconversion in pregnancy and risk of congenital infection.

The aim of the study was to describe the pregnancy outcome of a large cohort of women with toxoplasmosis seroconversion in pregnancy and to investigate the relation between maternal lymphadenopathy and risk of congenital toxoplasmosis (CT). This was a retrospective study involving women with confirmed toxoplasmosis seroconversion in pregnancy between 2001 and 2017. Women were clinically evaluated for lymphadenopathy and classified as follows: lymphadenopathy absent (L-) or lymphadenopathy present (L+). The mothers were treated and followed-up according to local protocol, and neonates were monitored at least for 1 year in order to diagnose CT. A total of 218 women (one twin pregnancy) were included in the analysis. Pregnancy outcome was as follows: 149 (68%) of children not infected, 62 (28.3%) infected, 4 (1.8%) first trimester termination of pregnancy, 2 (0.9%) first trimester miscarriages, and 3 (1.4%) stillbirths (of which one already counted in the infected cohort). 13.8% of women were L+ , and they were nearly three times more likely to have a child with CT compared to L- women (aOR, 2.90; 95%CI, 1.28-6.58). Moreover, the result was still statistically significant when the analysis was restricted to 81 children whose mothers were clinically examined and received treatment within 5 weeks from estimated time of infection. In conclusion, there is a positive association between L+ status in pregnant women, and risk of CT also confirmed when restricting the analysis to women with early diagnosis of seroconversion and treatment. This data could be very useful in counselling pregnant women with toxoplasmosis seroconversion and lead to direct a more specific therapeutic and diagnostic protocol.

A Novel Calcium-Dependent Protein Kinase 1 Inhibitor Potently Prevents Toxoplasma gondii Transmission to Foetuses in Mouse.

Treatments currently used to prevent congenital toxoplasmosis are non-specific of Toxoplasma gondii and have grievous side effects. To develop a more specific and less toxic drug, we have designed SP230, an imidazo[1,2-b]pyridazine salt targeting the Toxoplasma gondii calcium-dependent protein kinase 1 (TgCDPK1) and active against acute toxoplasmosis in mice. Efficiency of SP230 to inhibit foetal transmission of the parasite was evaluated in a mouse model of congenital toxoplasmosis. Swiss mice were infected at mid-pregnancy with tachyzoites or cysts of the ME49 strain of T. gondii by intraperitoneal and oral route, respectively, and treated with SP230 at 50 mg/kg for 5 days by the same routes. Parasite burden in organs of dams and in foetuses was measured by quantitative PCR. Intraperitoneal administration of SP230 drastically reduced the number of parasites (more than 97% of reduction) in the brain and lungs of dams, and led to a reduction of 66% of parasite burden in foetuses. Oral administration of SP230 was particularly efficient with 97% of reduction of parasite burdens in foetuses. SP230 did not impact number and weight of offspring in our conditions. This inhibitor of TgCDPK1 is a promising candidate for the development of alternative therapeutics to treat infected pregnant women.

Epidemiologic and Public Health Significance of Toxoplasma gondii Infections in Venison: 2009-2020.

Toxoplasma gondii infections are common in humans and animals worldwide. The ingestion of food or water contaminated with oocysts excreted by infected cats or ingestion of uncooked or undercooked meat containing tissue cysts of T. gondii are the 2 major modes of transmission of T. gondii. Deer are a popular game. Recently, outbreaks of clinical toxoplasmosis were reported in humans in North America linked to ingestion of undercooked venison. Here, we review prevalence, persistence of infection, clinical disease, epidemiology, and public health risks of T. gondii infections in deer and other cervids for the past decade. Estimates of worldwide serological prevalence are summarized individually for each species of deer, elk, moose, and caribou. Genetic diversity of 112 viable isolates of T. gondii from cervids is discussed, including its public health significance. Prevalence of T. gondii in deer is very high. Any part of a deer, including liver, spleen, and muscles, should be cooked thoroughly before human consumption.

Foodborne transmission of Toxoplasma gondii infection in the last decade. An overview.

Toxoplasmosis is a zoonotic disease of global distribution and importance. It is caused by the protozoan parasite Toxoplasma gondii, the only species in the Toxoplasma genus. This parasite can infect most warm-blooded animals, including humans and livestock. Main routes of transmission are by ingestion of tissue cysts in raw or undercooked meat of infected animals, ingestion of raw vegetables or water contaminated with T. gondii oocysts from cat feces, and transplacental. Around one-third of human beings are chronically infected with T. gondii. Most infections appear to be asymptomatic in immunocompetent persons, but toxoplasmosis can be fatal to the fetus and immunocompromised adults. Water and foodborne outbreaks have been caused by this parasite worldwide, but few are well documented. Importantly, T. gondii is a parasite of high importance in animal health, causing reproductive failure, particularly in small ruminants, and clinical toxoplasmosis in many species. This overview discusses the knowledge of T. gondii infections in the last decade focusing on the foodborne transmission of this parasite.

Toxoplasma gondii seroprevalence in beef cattle raised in Italy: a multicenter study.

Toxoplasmosis represents an important public health issue, with the consumption of raw or undercooked meat being a major way of human infection. The role of beef in the transmission of the parasite to humans is questioned due to lower quantity of tissue cysts compared with other meat-producing species. However, the habit of consuming raw beef is regionally diffused, and the risk posed by Toxoplasma gondii infection in cattle should not be overlooked. Therefore, to update information on T. gondii in cattle reared in Italy, a multicentric seroepidemiological survey was designed and implemented in four Northern regions (Liguria, Lombardy, Piedmont, and Trentino Alto Adige) and Sardinia. Overall, a convenience sampling was performed, collecting 1444 serum samples from 57 beef cattle herds. Thirteen beef breeds were sampled, besides cross-breed; bovines age varied from 3 months to over 12 years. Sera were tested with a commercial ELISA for the detection of anti-T. gondii antibodies. Individual and herd data were analyzed by binary logistic regression analysis. A T. gondii seroprevalence of 10.2% was recorded, with differences among regions and values ranging from 5.3% in Liguria to 18.6% in the Piedmont region (p value = 0.0001). Both young and adult animals and males and females tested positive, without any significant difference (age and gender: p value > 0.05). Lower seroprevalence values were recorded in cattle born in Italy (8.7%) if compared with animals imported from abroad (13.4%) (p value = 0.046). The spread of T. gondii in beef cattle destined to Italian consumers is confirmed, suggesting the need of continuous monitoring of the infection.

Methods to assess the effect of meat processing on viability of Toxoplasma gondii: towards replacement of mouse bioassay by in vitro testing.

Consumption of meat containing viable tissue cysts is considered one of the main sources of human infection with Toxoplasma gondii. In contrast to fresh meat, raw meat products usually undergo processing, including salting and mixing with other additives such as sodium acetate and sodium lactate, which affects the viability of T. gondii. However, the experiments described in the literature are not always performed in line with the current processing methods applied in industry. It was our goal to study the effect of salting and additives according to the recipes used by industrial producers. Mouse or cat bioassay is the 'gold standard' to demonstrate the presence of viable T. gondii. However, it is costly, time consuming and for ethical reasons not preferred for large-scale studies.Therefore, we first aimed to develop an alternative for mouse bioassay that can be used to determine the effect of processing on the viability of T. gondii tissue cysts. The assays studied were (i) a cell culture method to determine the parasite's ability to multiply, and (ii) a propidium monoazide (PMA) dye-based assay to selectively detect DNA from intact parasites. Processing experiments were performed with minced meat incubated for 20 h with low concentrations of NaCl, sodium lactate and sodium acetate. NaCl appeared to be the most effective ingredient with only one or two out of eight mice infected after inoculation with pepsin-digest of portions processed with 1.0, 1.2 and 1.6% NaCl. Results of preliminary experiments with the PMA-based method were inconsistent and did not sufficiently discriminate between live and dead parasites. In contrast, the cell culture method showed promising results, but further optimization is needed before it can replace or reduce the number of mouse bioassays needed. In future, standardised in vitro methods are necessary to allow more extensive testing of product-specific processing methods, thereby providing a better indication of the risk of T. gondii infection for consumers.

Toxoplasma-induced Behavioral Changes: An Aspecific Consequence of Neuroinflammation.

A key strategy that many parasites use to facilitate transmission involves behavioral modification of their hosts. Toxoplasma gondii has been taken as an example for this strategy. A recent study by Boillat et al. reported that attraction to predator odor following Toxoplasma infection is not specific to felines.

Neuroinflammation-Associated Aspecific Manipulation of Mouse Predator Fear by Toxoplasma gondii.

In rodents, the decrease of felid aversion induced by Toxoplasma gondii, a phenomenon termed fatal attraction, is interpreted as an adaptive manipulation by the neurotropic protozoan parasite. With the aim of understanding how the parasite induces such specific behavioral modifications, we performed a multiparametric analysis of T. gondii-induced changes on host behavior, physiology, and brain transcriptome as well as parasite cyst load and distribution. Using a set of complementary behavioral tests, we provide strong evidence that T. gondii lowers general anxiety in infected mice, increases explorative behaviors, and surprisingly alters predator aversion without selectivity toward felids. Furthermore, we show a positive correlation between the severity of the behavioral alterations and the cyst load, which indirectly reflects the level of inflammation during brain colonization. Taken together, these findings refute the myth of a selective loss of cat fear in T. gondii-infected mice and point toward widespread immune-related alterations of behaviors.

Comparative evaluation of loop-mediated isothermal amplification (LAMP) vs qPCR for detection of Toxoplasma gondii oocysts DNA in mussels.

The apicomplexan parasite Toxoplasma gondii can infect humans and cause toxoplasmosis. T. gondii has been highly prioritized among the foodborne parasites regarding its global impact on public health. Human infection can occur through multiple routes, including the ingestion of raw or undercooked food contaminated with T. gondii oocysts, such as fresh produce and bivalves. As filter-feeders, bivalves can accumulate and concentrate contaminants, including protozoan (oo)cysts. Although detection of T. gondii in different bivalves by molecular techniques (PCR and qPCR) has been achieved, routine application is currently limited by lack of sensitivity or equipment costs. Here, we describe the assessment of a loop-mediated isothermal amplification (LAMP)-based assay to detect T. gondii oocysts in spiked mussels. Detection limit was down to 5 oocysts/g in tissue and 5 oocyst/ml in hemolymph, and, under the experimental conditions tested, LAMP was found to provide a promising alternative to qPCR.

A review of toxoplasmosis in humans and animals in Turkey.

Infections by the protozoan parasite Toxoplasma gondii are widely prevalent in humans and animals in Turkey but little is known of the burden of their clinical toxoplasmosis. Many early papers on toxoplasmosis in Turkey were published in Turkish and often not available widely. Here, we review prevalence, clinical spectrum, epidemiology and diagnosis of T. gondii in humans and animals in Turkey. This knowledge should be useful to biologists, public health workers, veterinarians and physicians. Although one-third of the human population in Turkey is seropositive, the rate of congenital toxoplasmosis is unknown and no information is available in children 12 years old or younger. One large outbreak of acute toxoplasmosis has been reported in 14-18-year old school children in Turkey. An alarming rate (36%) of T. gondii tissue cysts were reported in tissues of sheep and water buffalo meats destined for human consumption; these reports require verification. Genetically, T. gondii strains from domestic cats and wild birds in Turkey were generally classical type II and III, like those prevalent in Europe. A separate genotype, Type 1 Africa, was isolated from two congenitally infected children and a domestic cat in Turkey.

Testing New Peptides From Toxoplasma gondii SAG1, GRA6, and GRA7 for Serotyping: Better Definition Using GRA6 in Mother/Newborns Pairs With Risk of Congenital Transmission in Mexico.

Toxoplasma gondii variant influences clinical profile in human congenital and ocular toxoplasmosis. Parasite genotyping represents a challenge due to insufficient amount of genetic material of the protozoan in the host samples, and isolates are hard to obtain, especially from pediatric patients. An alternative is serotyping, which is based on the presence of specific antibodies against polymorphic proteins related to virulence; the more widely used are GRA6 and GRA7, but most works report cross reactions among the classical strains (I, II, and III). We designed new peptides of GRA6, GRA7, and SAG1 proteins, with more SNPs among the three clonal strains than those previously designed. This was done by identifying BcR and polymorphic epitopes by means of bioinformatics; then we designed peptides with linkers joining the specific regions and predicted their 3D structure. With the commercial molecules synthesized on the basis of these designs, we tested 86 serum samples from 42 mother/newborn pairs and two congenitally infected newborns, by indirect ELISA. We implemented a strategy to determine the serotype based on scatter plots and a mathematical formula, using ratios among reactivity indexes to peptides. We found low frequency of samples reactive to GRA7 and SAG1, and cross reactions between GRA6 serotypes I and III; we modified these later peptides and largely improved distinction among the three clonal strains. The chronicity of the infection negatively affected the reactivity index against the peptides. Serotyping both members of the mother/child pair improves the test, i.e., among 26% of them only one member was positive. Serotype I was the most frequent (38%), which was congruent with previous genotyping results in animals and humans of the same area. This serotype was significantly more frequent among mothers who transmitted the infection to their offspring than among those who did not (53 vs. 8%, p = 0.04) and related to disease dissemination in congenitally infected children, although non-significantly. In conclusion, serotyping using the improved GRA6 peptide triad is useful to serotype T. gondii in humans and could be implemented for clinical management and epidemiological studies, to provide information on the parasite type in specific areas.

Patterns of Transmission and Sources of Infection in Outbreaks of Human Toxoplasmosis.

We report on apparent temporal progression of probable sources of infection and transmission routes for global human toxoplasmosis outbreaks as described in published articles. We searched the Scientific Electronic Library Online, Web of Science, PubMed, and Scopus databases for articles on Toxoplasma, toxoplasmosis, and outbreaks. We found that transmission routes for Toxoplasma gondii varied by decade. In the 1960s and 1990s, toxoplasmosis outbreaks mainly occurred through ingestion of cysts in meat and meat derivatives; in the 1980s, through milk contaminated with tachyzoites; in 2000, due to the presence of oocysts in water, sand, and soil; and in 2010, due to oocysts in raw fruits and vegetables. Our study suggests a possible change in the epidemiology of reported toxoplasmosis outbreaks. Because of this change, we suggest that greater attention be paid to the disinfection of vegetables, as well as to the quality of water used for drinking and irrigation.

Disseminated toxoplasmosis associated with hemophagocytic syndrome after kidney transplantation: A case report and review.

Disseminated toxoplasmosis is infrequent after kidney transplant transmission but life-threatening because of a lack of diagnostic suspicion as well as specific chemoprophylaxis recommendations. Solid organ transplantation has resulted in few cases of disseminated toxoplasmosis presenting with associated hemophagocytic syndrome. Herein, we report, within the context of a donor/receiver mismatch, a case of a toxoplasmosis associated with hemophagocytic syndrome in a kidney transplant recipient. Molecular and serological investigations confirmed Toxoplasma gondii transmission through the kidney graft.

Psicofísica visual em caso de toxoplasmose ocular congênita / Visual psychophysics of congenital ocular toxoplasmosis case

Resumo A toxoplasmose ocular congênita é uma manifestação da infecção pelo parasita Toxoplasma gondii que ocorrer por meio placentário. Essa doença pode provocar importantes sequelas visuais. Este trabalho descreve um estudo de caso que utilizou avaliação psicofísica visual para descrever alterações funcionais decorrentes da toxoplasmose ocular congênita. A avaliação foi realizada em paciente de 30 anos, sexo masculino, residente em São Luís (MA), hígido com histórico da mãe ter apresentado infecção por toxoplasmose no período gestacional. Somente aos 26 anos foi feita uma avaliação médica detalhada que descreveu lesão na fóvea do olho direito. Na avaliação clínica clássica e na avaliação psicofísica visual, o paciente apresentou visão normal para o olho esquerdo. O olho direito apresentou baixa acuidade visual (valor decimal: 0,028), campo visual com escotomas localizados até 20º de ângulo visual e alteração da visão de cor. O estudo fornece informações médicas seguras e relevantes para o diagnóstico de toxoplasmose ocular congênita utilizando testes eficazes, de baixo custo e boa portabilidade, possibilitando uma alternativa de diagnóstico funcional para ser aplicada em locais de difícil acesso pelo interior do Brasil.

Abstract Congenital ocular toxoplasmosis is a manifestation of infection by the parasite Toxoplasma gondii that occurs through the placenta. This disease can lead to important visual sequelae. This paper describes a case report that uses visual psychophysics for the alterations of congenital ocular toxoplasmosis. The evaluation was performed in a 30-year-old man, a resident of São Luís (MA), with a history of his mother have had toxoplasmosis in the gestational period. Only at 26 years-old he did the detailed medical evaluation that described a lesion the fovea of the right eye. In the classic clinical examination and in visual psychophysical evaluation, the patient presented normal vision for the left eye. The right eye had low visual acuity (decimal value: 0.028), visual field with scotomas up to 20º of visual angle and alteration of color vision. The study offers safe and relevant medical information for the diagnosis of congenital ocular toxoplasmosis using a low-cost evaluation and with good portability, allowing a functional diagnostic alternative to be applied in places difficult to access in the interior of Brazil.

Prevalencia de toxoplasmosis en estudiantes de la Universidad Nacional de Chimborazo en Ecuador / Prevalence of toxoplasmosis in students of the National University of Chimborazo in Ecuador

Introducción: La infección por Toxoplasma gondii durante la edad fértil de la mujer, es un problema de salud no bien entendido en la población, círculos médicos y decisores dentro de los sistemas de salud; al no considerar importante las formas de adquirirla y el riesgo que implica infectarse durante el embarazo. En Ecuador no existen datos consistentes de la circulación y endemicidad de esta parasitosis, siendo esta la situación problémica el motivo de este trabajo. Objetivo: Conocer la seroprevalencia de Toxoplasma gondii en mujeres jóvenes en edad fértil y su relación con el nivel de conocimiento sobre la enfermedad. Métodos: Se evaluó el comportamiento serológico de T. gondii en 105 muestras de sueros de alumnas de la Universidad Nacional de Chimborazo de la Carrera de Laboratorio Clínico e Histopatológico, mediante la determinación de IgG anti T. gondii utilizando la Técnica de Quimioluminiscencia. Resultados: 38 alumnas (36,0 por ciento) resultaron ser positivas para anticuerpos contra T. gondii, lo que indica el contacto con el parásito en algún momento de su vida. La falta de conocimiento sobre las principales vías de contagio puede ser la causa de la seropositividad demostrada, lo que representa un riesgo para las seronegativas durante el embarazo. Conclusiones: Se demuestra seroprevalencia de la infección por T. gondii en la población estudiada y la endemicidad del parásito(AU)

Introduction : Toxoplasma gondii is the infection that occurs during the fertile age of women and is a health problem not well understood by the people, doctors and leaders of the health systems of some countries; as it does not consider important the ways of acquiring it and the risk involved in becoming infected during pregnancy. In Ecuador there aren´t consistent data on the circulation and endemicity of this parasitosis, being this problematic situation the reason for this work. Objective : The purpose of the present study was to determine the seroprevalence of Toxoplasma gondii in young women of childbearing age and their relation with the level of knowledge about the disease. Methods: The serological behavior of T. gondii was evaluated in 105 samples of sera from the National University of Chimborazo of the Clinical and Histopathological Laboratory, by the determination of IgG anti T. gondii using the Chemiluminescence Technique. Results: Of the study population, 38 students (36.0 percent) were found to be positive for antibodies to T. gondii, indicating contact with the parasite at some point in their life. The demonstrated seropositivity may be due to the lack of knowledge about the main routes of infection, the risk of being seronegative during pregnancy and the high endemicity of the parasite. Conclusions : The seroprevalence of T. gondii infection in the studied population were demonstrated(AU)

Human placental PPAR-γ and SOX-2 expression in serologically proved toxoplasmosis.

To explore PPAR-γ and SOX-2 transcription factors expression in placenta according to maternal anti-Toxoplasma gondii serological profile during pregnancy and pregnancy outcome. The study included 240 placentas, grouped according to IgM and IgG serostatus and then subgrouped according to pregnancy outcome that varied between miscarriages, premature labour, stillbirth and giving birth to CNS anomaly or apparently healthy neonates. Samples were H&E stained and histopathologically scored blindly. PPAR-γ expression was measured by ELISA, while SOX-2-positive nuclei were stained immunohistochemically to be calculated by ImageJ. The mean pathological score was significantly higher in IgM+ve and IgG rising than IgG-ve and persistent low groups. Former groups showed significantly higher PPAR-γ (mean = 258.63, 227.11). However, PPAR-γ was higher in apparently healthy neonate subgroups. SOX-2 was significantly lower in IgM+ve and IgG rising groups (mean = 12.87, 43.13) and associated with obvious fibrosis. SOX-2 lowest count was in CNS anomaly subgroup. PPAR-γ and SOX-2 changes may give clues of how Toxoplasma induces pathogenesis during vertical transmission. Triggering PPAR-γ expression may be a tool to downregulate the inflammatory response and establish a metabolically permissive cellular environment for Toxoplasma persistence. Low SOX-2 is suspected to disturb placental mesenchymal stem cells pluripotency and neuroectoderm development.

Toxoplasmosis diseminada en un paciente con trasplante de corazón a pesar de la profilaxis con trimetoprim-sulfametoxazol / Disseminated toxoplasmosis in a heart transplant patient despite cotrimoxazole prophylaxis: A case report

Resumen Se reporta el caso de un paciente de sexo masculino, de 61 años de edad, quien ocho meses después de someterse a un trasplante de corazón presentó una enfermedad sistémica con compromiso del sistema nervioso central y del sistema inmunológico, así como de pulmón, riñón, colon y piel, y a quien finalmente se le diagnosticó toxoplasmosis diseminada, a pesar de haber recibido profilaxis con trimetoprim-sulfametoxazol, debido a que el órgano provenía de un donante positivo para toxoplasmosis siendo él un receptor negativo. Se discuten las opciones de profilaxis en nuestro medio.

Abstract We report the case of a 61 year-old male who underwent heart transplantation eight months before developing a systemic condition with central nervous system, lung, kidney, colonic, cutaneous, and hematologic involvement, found to be secondary to a systemic toxoplasmosis despite co-trimoxazole prophylaxis in a previous-to-transplant seronegative patient receiving a heart from a seropositive donor. A review of prophylactic options in our environment is discussed.

[Good's syndrome and congenital toxoplasmosis due to maternal reactivation during pregnancy]. / Syndrome de Good et toxoplasmose congénitale secondaire à une réactivation maternelle pendant la grossesse.

INTRODUCTION: Good syndrome is a rare condition in which thymoma is associated with hypogammaglobulinemia. It is characterized by an increased susceptibility to infections. CASE REPORT: We report a woman with Good's syndrome diagnosed after severe congenital toxoplasmosis in her daughter, even though she was immunized against this infection during pregnancy. CONCLUSION: This presentation is very unusual by its early diagnosis and to our knowledge is the first report of parasitic infection in this syndrome.

Impaired health status and increased incidence of diseases in Toxoplasma-seropositive subjects - an explorative cross-sectional study.

The global seroprevalence of latent toxoplasmosis is estimated to be higher than 30%. The presence of slowly dividing parasites in tissue cysts located mainly in immunoprivileged organs was long considered asymptomatic. Recently, many studies have shown that latent Toxoplasma infections could have serious impacts on human health. Here we ran a cross-sectional study in a population of 1486 volunteers. The results showed that 333 infected subjects scored worse than 1153 controls in 28 of 29 health-related variables. Similarly, they reported higher rates of 77 of a list of 134 disorders reported by at least 10 participants of the study. Toxoplasmosis was associated most strongly with musculoskeletal (τ = 0·107, P < 0·0005), followed by neurological (τ = 0·088, P < 0·0005), immune (τ = 0·085, p < 0·0005), metabolic (τ = 0·079, P < 0·0005), respiratory (τ = 0·068, P = 0·0001), allergic (τ = 0·053, P = 0·004), digestive system (τ = 0·052, P = 0·004) and mental health disorders (τ = 0·050, P = 0·008). Results of the present cohort study, along with the previous data from many case-control studies or ecological studies suggest that latent toxoplasmosis represents a large and so far underrated public health problem.