Toxoplasmosis in animals and humans: a neglected zoonotic disease in Bangladesh

Toxoplasmosis, caused by Toxoplasma gondii, is a zoonotic disease that affects a wide range of warm-blooded animals, including humans. The parasite undergoes both sexual and asexual reproduction in intermediate hosts (humans and animals) and definitive hosts (cats). Transmission in humans occurs through consuming oocyst-contaminated water, fruits, vegetables, and raw or undercooked meats. In Bangladesh, several factors contribute to an increased risk of contracting toxoplasmosis. The parasite is reported to cause diseases among livestock such as goats and sheep in this country, and it has also been associated with some human illnesses. Toxoplasmosis prevalence varies significantly worldwide, with developing countries like Bangladesh experiencing higher rates. Diagnostic methods include both conventional non-DNA-based tests and molecular detection techniques, while treatment options involve using antiparasitic drugs like sulfadiazine and pyrimethamine. To control toxoplasmosis, essential steps include improving sanitation, promoting safe food handling, and educating the public about risks related to cat ownership and undercooked meat consumption. Implementing prenatal screening and treatment is also important. With the growing popularity of pet ownership in urban areas, it becomes essential to emphasize the veterinary and public health significance of toxoplasmosis in Bangladesh. This article comprehensively reviews various aspects of toxoplasmosis, with a specific focus on the situation in Bangladesh.

High prevalence and diversity of Toxoplasma gondii DNA in feral cat feces from coastal California

Toxoplasma gondii is a zoonotic parasite that can cause severe morbidity and mortality in warm-blooded animals, including marine mammals such as sea otters. Free-ranging cats can shed environmentally resistant T. gondii oocysts in their feces, which are transported through rain-driven runoff from land to sea. Despite their large population sizes and ability to contribute to environmental oocyst contamination, there are limited studies on T. gondii oocyst shedding by free-ranging cats. We aimed to determine the frequency and genotypes of T. gondii oocysts shed by free-ranging domestic cats in central coastal California and evaluate whether genotypes present in feces are similar to those identified in sea otters that died from fatal toxoplasmosis. We utilized a longitudinal field study of four free-ranging cat colonies to assess oocyst shedding prevalence using microscopy and molecular testing with polymerase chain reaction (PCR). T. gondii DNA was confirmed with primers targeting the ITS1 locus and positive samples were genotyped at the B1 locus. While oocysts were not visualized using microscopy (0/404), we detected T. gondii DNA in 25.9% (94/362) of fecal samples. We genotyped 27 samples at the B1 locus and characterized 13 of these samples at one to three additional loci using multi locus sequence typing (MLST). Parasite DNA detection was significantly higher during the wet season (16.3%, 59/362) compared to the dry season (9.7%; 35/362), suggesting seasonal variation in T. gondii DNA presence in feces. High diversity of T. gondii strains was characterized at the B1 locus, including non-archetypal strains previously associated with sea otter mortalities. Free-ranging cats may thus play an important role in the transmission of virulent T. gondii genotypes that cause morbidity and mortality in marine wildlife. Management of free-ranging cat colonies could reduce environmental contamination with oocysts and subsequent T. gondii infection in endangered marine mammals and people.

Diagnosis of Toxoplasmosis Using Surface Antigen Grade 1 Detection by ELISA, Nano-Gold ELISA, and PCR in Pregnant Women

Introduction

The accurate diagnosis of toxoplasmosis has critical importance in pregnant women. Nanotechnology and molecular biology are making possible opportunities for accurate and rapid diagnosis of many infectious diseases.

Aim and Methods

The aim of our study was to compare nano-gold ELISA with ELISA and PCR for diagnosis of toxoplasmosis using Toxoplasma surface antigen grade 1 (SAG1) in pregnant women seeking antenatal care in outpatient clinics.

Results

PCR showed the highest diagnostic values than nano-gold ELISA and ELISA regarding sensitivity (97.3% versus 89.2% and 83.8%); specificity (100% versus 94% and 88%); and diagnostic accuracy (98.9% versus 91.95% and 86.2%), respectively. There is no statistical difference between PCR and nanogold ELISA results.

Discussion

Nano-gold ELISA had a significant improvement in diagnosis than the traditional ELISA method. Most likely with the assistance of nanoparticles, more antibodies enter the antigen-antibody complex because of the considerable improvement in the surface area of nano-gold particles.

Conclusion

Although PCR had higher diagnostic values than nano ELISA, nano ELISA is cheaper and easier than PCR. We recommend nano-gold ELISA with SAG1 as a promising technique in the diagnosis of toxoplasmosis and survey studies.

A Cross-Sectional Study on the Association Between Risk Factors of Toxoplasmosis and One Health Knowledge in Pakistan

Toxoplasmosis is a zoonotic disease caused by Toxoplasma gondii, a protozoan that infects warm-blooded animals and humans. Approximately one third of the global population is infected by T. gondii. We conducted a cross-sectional study to assess the risk factors and One Health knowledge of toxoplasmosis in Rawalpindi and Islamabad, Pakistan. From July through December 2020, we collected data using questionnaires. The results showed that 60% of participants had heard or read about the disease, 23.3% of participants had no knowledge about the disease, and 16.8% participants were not sure about the disease. More than half of the participants (53.3%) reported that toxoplasmosis was caused by toxins, 5.3% reported that toxoplasmosis was an animal disease, 13.8% reported that toxoplasmosis was a human disease, 65.8% reported that it was both an animal and human disease, and 15.3% reported that it was neither an animal nor a human disease. Approximately 80.5% of participants reported that individuals acquired toxoplasmosis by changing cat litter. Our study findings revealed a low level of knowledge and awareness about toxoplasmosis among males. Therefore, there should be awareness programs to educate individuals about the risks of this deadly disease and to provide information on the major routes of transmission.

Dynamics and epidemiology of Toxoplasma gondii oocyst shedding in domestic and wild felids

Oocyst shedding in domestic and wild felids is a critical yet understudied topic in Toxoplasma gondii ecology and epidemiology that shapes human and animal disease burden. We synthesized published literature dating from the discovery of felids as the definitive hosts of T. gondii in the 1960s through March 2021 to examine shedding prevalence, oocyst genotypes, and risk factors for shedding. Oocyst shedding prevalence in many geographic regions exceeded the commonly accepted 1% reported for domestic cats; crude prevalence from cross-sectional field studies of domestic cat shedding ranged from 0% in Australia to 18.8% in Africa, with greater variation in reports of oocyst shedding in free-ranging, wild felids. Shedding in wild felid species has primarily been described in captive animals, with attempted detection of oocyst shedding reported in at least 31 species. Differences in lifestyle and diet play an important role in explaining shedding variation between free-ranging unowned domestic cats, owned domestic cats and wild felids. Additional risk factors for shedding include the route of infection, diet, age and immune status of the host. It is widely reported that cats only shed oocysts after initial infection with T. gondii, but experimental studies have shown that repeat oocyst shedding can occur. Factors associated with repeat shedding are common amongst free-ranging felids (domestic and wild), which are more likely to eat infected prey, be exposed to diverse T. gondii genotypes, and have coinfections with other parasites. Repeat shedding events could play a significant yet currently ignored role in shaping environmental oocyst loading with implications for human and animal exposure. Oocyst presence in the environment is closely linked to climate variables such as temperature and precipitation, so in quantifying risk of exposure, it is important to consider the burden of T. gondii oocysts that can accumulate over time in diverse environmental matrices and sites, as well as the spatial heterogeneity of free-ranging cat populations. Key directions for future research include investigating oocyst shedding in under-sampled regions, genotyping of oocysts detected in faeces and longitudinal studies of oocyst shedding in free-ranging felids.

Seroprevalence of Toxoplasma gondii in outdoor dogs and cats in Bangkok, Thailand

The aim of this study was to estimate the seroprevalence and risk factors associated with Toxoplasma gondii exposure in dogs and cats from Bangkok, Thailand. Blood samples from 318 dogs and 321 cats were tested for T. gondii antibodies by modified agglutination test (cut-off 1:25). Additionally, 18 dogs and 20 cats were longitudinally sampled for T. gondii antibodies during the same study period, between June and July 2019. The overall seroprevalence in dogs and cats was 7.9% (25/318; 95% CI 4.9–10.8%) and 18.7% (95% CI 14.4–23.0%), respectively. For dogs, risk factors identified were being a mixed-breed animal and living totally outdoors, while increasing age was shown to be a risk factor for cats. Seroconversion was not detected and titres from positive animals remained constant over longitudinal study. The present study indicates that there is a prominent presence of T. gondii in urban and peri-urban areas of Bangkok, suggesting that outdoor dogs and cats should be considered as a possible risk factor for humans.

Copro-molecular diagnosis of the Toxoplasmatinae subfamily in dog and cat populations in northern Iran

OBJECTIVES

The oocysts of the Toxoplasmatinae subfamily (Neospora caninum, Hammondia hammondi and H. heydorni, and Besnoitia besnoiti) are morphologically similar to Toxoplasma gondii, and indistinguishable from each other. This study investigated the prevalence of the Toxoplasmatinae subfamily in dog and cat fecal samples using a nested polymerase chain reaction method.

METHODS

Overall, 200 fecal samples from domestic dogs (n=120) and cats (n=80) were collected from 15 farms in northern Iran. The samples were homogenized in 2.5% potassium dichromate solution and subsequently concentrated with sucrose solution. DNA was extracted from samples using a genomic DNA kit. Specific primers and the 18S rDNA gene were used to screen and detect all Toxoplasmatinae oocysts.

RESULTS

Overall, 2.5% (3 of 120) and 22.5% (18 of 80) of the fecal samples collected from dogs and cats were infected with Toxoplasmatinae. In dogs, 2 samples were positive for N. caninum and 1 sample was positive for T. gondii. In cats, all 18 positive samples belonged to T. gondii. No contamination with H. heydorni was observed in dog fecal samples or H. hammondi and B. besnoiti in cat fecal samples. A phylogenetic analysis revealed that the T. gondii (cat) and N. caninum (dog) found had similarities with parasites reported from other regions of the world.

CONCLUSIONS

This is the first study to provide data on the epidemiology of Toxoplasmatinae oocysts in Iran. The findings suggest that public-health monitoring for the effective control of feces from cats and dogs and improved pet hygiene habits are needed.

A Review on the Present Advances on Studies of Toxoplasmosis in Eastern Africa

Toxoplasmosis is a zoonotic infection caused by the protozoan parasite, Toxoplasma gondii. It was discovered over 100 years ago and is credited as the most successful parasitic organism worldwide, able to infect and multiply in all warm blooded animals including an estimated 2.3 billion people. Toxoplasmosis is asymptomatic in immunocompetent individuals. Infection in the developing fetus and immunocompromised individuals can cause severe clinical disease. Toxoplasmosis is also a major cause of reproductive failure in livestock. The economic impact of toxoplasmosis is believed to be substantial. Factors associated with toxoplasmosis infection have been defined. Eastern Africa region is a high-risk area mainly due to the close association of humans and livestock as well as sociocultural practices, poor environmental hygiene, and poverty. The present paper provides a narrative review of published data on toxoplasmosis in Eastern Africa.

Toxoplasma gondii infection in backyard chickens (Gallus domesticus): Seroprevalence and associated risk factors in Northwest Ethiopia

Limited data is accessible about the seroprevalence of Toxoplasma gondii infection in backyard (free-range) chickens in Ethiopia. This cross-sectional study was carried out from November 2018 to April 2019 to estimate the seroprevalence and assess associated risk factors of T. gondii infection in backyard chickens in Northwest Ethiopia. Serum samples were collected from 384 backyard chickens. Toxoplasma gondii antibodies were assayed using Toxo-Latex slide agglutination test. Seropositivity for T. gondii antibodies was confirmed in 72.4% of 384 birds. Altitude, presence of cat and dog around the house, age, breed and water source were considered as potential risk factors (p < .05) associated with Toxoplasma seropositivity in this study. But, sex was not identified as a predictor for Toxoplasma infection even though higher seroprevalence was observed in females (73.7%) than males (69.3%). In conclusion, this study indicates a high prevalence of T. gondii infection in backyard chickens in Northwest Ethiopia. Therefore, further works on epidemiology, bioassay, isolation and genetic characterization of the pathogen are imperative. It also warrants an action to prevent and control T. gondii infection in backyard chickens that could serve as an important intermediate host and pose a potential threat for consumers.

All about toxoplasmosis in cats: the last decade

Toxoplasma gondii infections are common in humans and animals worldwide. Toxoplasmosis continues to be of public health concern. Cats (domestic and wild felids) are the most important host in the epidemiology of toxoplasmosis because they are the only species that can excrete the environmentally resistant oocysts in feces. Cats can excrete millions of oocysts and a single cat can spread infection to many hosts. The present paper summarizes information on prevalence, persistence of infection, clinical signs, and diagnosis of T. gondii infections in domestic and wild cats for the past decade. Special emphasis is paid to genetic diversity of T. gondii isolates from cats. Review of literature indicates that a unique genotype (ToxoDB genotype #9 or Chinese 1) is widely prevalent in cats in China and it has been epidemiologically linked to outbreaks of clinical toxoplasmosis in pigs and deaths in humans in China; this genotype has rarely been detected in other countries. This review will be of interest to biologists, parasitologists, veterinarians, and public health workers.

Seroprevalence of Toxoplasma gondii infection in sheep in Inner Mongolia Province, China

Toxoplasma gondii is an important zoonotic parasite that can infect almost all warm-blooded animals, including humans, and infection may result in many adverse effects on animal husbandry production. Animal husbandry in Inner Mongolia is well developed, but data on T. gondii infection in sheep are lacking. In this study, we determined the seroprevalence and risk factors associated with the seroprevalence of T. gondii using an indirect enzyme-linked immunosorbent assay (ELISA) test. A total of 1853 serum samples were collected from 29 counties of Xilin Gol League (n = 624), Hohhot City (n = 225), Ordos City (n = 158), Wulanchabu City (n = 144), Bayan Nur City (n = 114) and Hulunbeir City (n = 588). The overall seroprevalence of T. gondii was 15.43%. Risk factor analysis showed that seroprevalence was higher in sheep ≥12 months of age (21.85%) than that in sheep <12 months of age (10.20%) (p < 0.01). Seroprevalence was higher in male sheep (18.76%) than females (12.80%) (p < 0.01). Barn-feeding sheep (23.13%) had higher prevalence than grazing sheep (10.94%) (p < 0.01). The seroprevalence was significantly different in different districts (p < 0.01). This study shows that sheep are exposed to T. gondii in Inner Mongolia, and provides a data reference for public health and disease control.

A serological and parasitological study of Toxoplasma gondii infection in stray cats of Mashhad, Khorasan Razavi province, Iran

The aim of the present study was to determine seroprevalence of Toxoplasma gondii infection in stray cats and correlation with oocyst shedding and IFN-γ concentration. From April to August 2016, one hundred fifty-nine stray cats were captured from various localities in Mashhad area. The blood and fecal samples were collected from each cat. The serum samples were examined to detect antibodies against T. gondii infection by ELISA assay and the fecal samples were microscopically examined for T. gondii oocyst detection. The concentration changes of IFN-γ in serum samples of seropositive and seronegative cats were measured using ELISA kit. The results showed that 59.12% (94/159) of cats had antibodies against T. gondii infection. The seroprevalence of T. gondii infection in the adult cats above three years olds was higher than other groups. Regarding gender, month and region factors, the difference of seroprevalence of T. gondii infection was not significant. In this study, the Toxoplasma/Hammondia like oocyst (THLO) were detected in 2.56% (4/156) in fecal samples of one seropositive and three seronegative cats. Results also showed that the mean value for IFN-γ concentration in the seropositive cats was significantly higher than that of the seronegative cats. Based on the results, the high percentages of stray cats were infected with T. gondii in this area. The IFN-γ concentration of seropositive cats was higher than that of the seronegative cats.

Detection of Toxoplasma gondii copro-prevalence by polymerase chain reaction using repetitive 529 bp gene in feces of pet cats (Felis catus) in Yogyakarta, Indonesia

Aim:

The aim of this research was to determine the copro-prevalence of Toxoplasma gondii using polymerase chain reaction (PCR) with repetitive 529 bp gene and to construct the phylogenetic tree of Toxoplasma oocyst from pet cats in Yogyakarta.

Materials and Methods:

9 of 132 pet cat samples which serologically positive for Toxoplasma were used in this research. To determine the copro-prevalence of T. gondii in pet cat, 10 g of feces samples taken from practitioners and household cats in Yogyakarta were used in the PCR method utilizing repetitive 529 bp gene sequences.

Results:

The result shows that copro-prevalence by PCR using repetitive 529 bp gene was 33.3% (3/9). The phylogenetic tree of Toxoplasma grouped into two clades, which clade 1 consists of Toxoplasma isolates collected from pet cats in Yogyakarta Indonesia and T. gondii isolates from China and in clade 2 consist of the T. gondii isolates from India.

Conclusion:

Copro-prevalence of T. gondii in pet cats in Yogyakarta by means of PCR using repetitive 529 bp gene is around 33.3%.

Advantages of bioconjugated silica-coated nanoparticles as an innovative diagnosis for human toxoplasmosis

Nanotechnology is a promising arena for generating new applications in Medicine. To successfully functionalised nanoparticles for a given biomedical application, a wide range of chemical, physical and biological factors have to be taken into account. Silica-coated nanoparticles, (SiO2NP) exhibit substantial diagnostic activity owing to their large surface to volume ratios and crystallographic surface structure. This work aimed to evaluate the advantage of bioconjugation of SiO2NP with PAb against Toxoplasma lyzate antigen (TLA) as an innovative diagnostic method for human toxoplasmosis. This cross-sectional study included 120 individuals, divided into Group I: 70 patients suspected for Toxoplasma gondii based on the presence of clinical manifestation. Group II: 30 patients harboring other parasites than T. gondii Group III: 20 apparently healthy individuals free from toxoplasmosis and other parasitic infections served as negative control. Detection of circulating Toxoplasma antigen was performed by Sandwich ELISA and Nano-sandwich ELISA on sera and pooled urine of human samples. Using Sandwich ELISA, 10 out of 70 suspected Toxoplasma-infected human serum samples showed false negative and 8 out of 30 of other parasites groups were false positive giving 85.7% sensitivity and 84.0% specificity, while the sensitivity and specificity were 78.6% and 70% respectively in urine samples. Using Nano-Sandwich ELISA, 7 out of 70 suspected Toxoplasma-infected human samples showed false negative results and the sensitivity of the assay was 90.0%, while 4 out of 30 of other parasites groups were false positive giving 92.0% specificity, while the sensitivity and specificity were 82.6% and 80% respectively in urine samples. In conclusion, our data demonstrated that loading SiO2 nanoparticles with pAb increased the sensitivity and specificity of Nano-sandwich ELISA for detection of T.gondii antigens in serum and urine samples, thus active (early) and light infections could be easily detected.

Detection of Toxoplasma gondii in faeces of privately owned cats using two PCR assays targeting the B1 gene and the 529-bp repetitive element

Toxoplasma gondii infection is a worldwide parasitic zoonosis with a high-health risk for humans. The key epidemiological role played by felids is related to oocyst shedding. The present study compared two amplification protocols for the molecular diagnosis of Toxoplasma infection in owned cats. A total of 78 owned cats referred to an Italian university-teaching hospital and exposed to various T. gondii-associated risk factors were sampled for blood and faeces. Faecal specimens were processed by flotation and tested using 2 copro-PCRs targeting the widely used B1 gene and the 529-bp repetitive element (RE). The sera were tested by the indirect immunofluorescent antibody test (IFAT) for the detection of immunoglobulins against T. gondii. Sixteen faeces (20.52%) tested positive for T. gondii DNA; 12 samples were positive only at B1-PCR, two at 529-bp RE-PCR and two at both genetic targets (overall agreement = 82.11%). The amplicons obtained were sequenced, and the Basic Local Alignment Search Tool analysis showed a high homology with the T. gondii strains available in reference databases. Two stool samples were microscopically positive for T. gondii-like oocysts and also tested positive by both B1 and 529-bp RE-PCRs. Thirty-three (42.3%) sera tested positive for antibodies; of which, seven were found to have T. gondii DNA-positive results using the B1 genetic target (overall agreement = 57.77%). The amplification sets targeting B1 and 529-bp RE showed substantially different yields. Further research is needed to better understand the significance and the sensitivities of using these multi-copy-targeted molecular methods from cat faeces before being used for routine diagnosis.

Seroprevalence of and Risk Factors for Toxoplasma gondii Infection in Cats in Estonia

In Estonia, northeastern Europe, Toxoplasma gondii seroprevalence in humans has not declined, in contrast to many other countries. The reasons for this are unknown. Domestic cats are important hosts in the epidemiology of the parasite, but information on local feline T. gondii infections has been lacking. An epidemiological cross-sectional study was conducted to estimate the seroprevalence of T. gondii and the risk factors associated with seropositivity in cats in Estonia. Surplus from blood samples that had been collected for unrelated diagnostic purposes from 306 pet cats and 184 shelter cats were analyzed for anti-T. gondii immunoglobulin G antibodies by using a direct agglutination test. Two questionnaires were designed to reveal relevant risk factors for seropositivity. The overall seroprevalence of T. gondii in cats in Estonia was 60.8%. Older age, outdoor access, hunting, living outside the city in the countryside, and not being a purebred cat were among the risk factors associated with seropositivity. T. gondii is highly prevalent in domestic cats in Estonia. This suggests that the environment has been contaminated with T. gondii. Seropositivity indicates previous oocyst shedding, and most of the cats had outdoor access. The increase in T. gondii seroprevalence with age indicates acquired infections, and most of the risk factors were lifestyle-related. Cat owners could diminish the risk of T. gondii infection and also limit the spread of the parasite by not allowing their cats to roam free.

Diagnosis of toxoplasmosis and typing of Toxoplasma gondii

Toxoplasmosis, caused by the obligate intracellular protozoan Toxoplasma gondii, is an important zoonosis with medical and veterinary importance worldwide. The disease is mainly contracted by ingesting undercooked or raw meat containing viable tissue cysts, or by ingesting food or water contaminated with oocysts. The diagnosis and genetic characterization of T. gondii infection is crucial for the surveillance, prevention and control of toxoplasmosis. Traditional approaches for the diagnosis of toxoplasmosis include etiological, immunological and imaging techniques. Diagnosis of toxoplasmosis has been improved by the emergence of molecular technologies to amplify parasite nucleic acids. Among these, polymerase chain reaction (PCR)-based molecular techniques have been useful for the genetic characterization of T. gondii. Serotyping methods based on polymorphic polypeptides have the potential to become the choice for typing T. gondii in humans and animals. In this review, we summarize conventional non-DNA-based diagnostic methods, and the DNA-based molecular techniques for the diagnosis and genetic characterization of T. gondii. These techniques have provided foundations for further development of more effective and accurate detection of T. gondii infection. These advances will contribute to an improved understanding of the epidemiology, prevention and control of toxoplasmosis.

A meta-analysis of the prevalence of Toxoplasma gondii in animals and humans in Ethiopia

BACKGROUND

Toxoplasmosis is a worldwide zoonosis. The objectives of this study were to estimate the prevalence and assess the potential risk factors of Toxoplasma gondii infections in animals and humans in Ethiopia by using meta-analytical methods.

METHODS

Published studies on T. gondii in animals and humans in Ethiopia were searched in Medline, Google Scholar and the lists of references of articles. Eligible studies were selected by using inclusion and exclusion criteria. The risks of within and across study biases, and the variations in prevalence estimates attributable to heterogeneities were assessed. Pooled prevalence was estimated by the DerSimonian and Laird random effects model.

RESULTS

Thirty two studies were eligible and data from 5689 animals and 5718 humans were used for quantitative syntheses. The pooled IgG seroprevalence in cats, small ruminants and humans were estimated at 87.72% (95% CI = 78.63, 93.28), 34.59% (95% CI = 21.08, 51.12) and 74.73% (95% CI = 61.85, 84.36), respectively. The odds of infections were higher in pregnant than in non pregnant women (OR = 3.96), in individuals that had contact with cats than those with no contact (OR = 2.53), and in urban than in rural inhabitants (OR = 2.06).

CONCLUSIONS

Toxoplasmosis is highly prevalent and could be a cause of considerable reproductive wastage in small ruminants and multiple diseases in humans in Ethiopia. Public education on preventive measures could help reduce the transmission of the parasite to humans.

First report on seroepidemiology of Toxoplasma gondii infection in pigs in Central Ethiopia

Background

Toxoplasma gondii is one of the most widely prevalent cyst forming Apicomplexan parasites with significant impact on animal production particularly in sheep, goats and pigs. The objectives of this cross-sectional study were to estimate the seroprevalence and to assess risk factors of Toxoplasma gondii infection in pigs. A systematic random sampling technique was used to collect 402 blood samples from pigs in Central Ethiopia. Direct Agglutination Test (DAT) was used to test sera. A questionnaire survey was made to assess potential risk factors and knowledge of farm attendants about toxoplasmosis.

Results

An overall seroprevalence of 32.1% [95% confidence interval (CI): 27.6%-36.9%] was found. Multivariable logistic regression analysis showed that extensively managed pigs (39.7%) are nearly twice (adjusted odds ratio [aOR]:=1.91, 95% CI: 1.01, 3.63) at higher risk of acquiring toxoplasmosis than intensively managed pigs (30.5%). Pigs supplied with feed containing animal byproducts had nearly four times (OR = 3.84, 95% CI: 2.01, 7.36) higher risk of acquiring T. gondii infection. Most of the farm attendants had little knowledge of health risks due to cats, neither to human nor to animals. Absence of rodent control, high neonatal mortality and history of abortion were found among herds of the studied pig farms.

Conclusions

T. gondii infections in pigs are wide spread. Extensive management systems and pig feed types containing animal byproducts are independent predictors of T. gondii seropositivity. The high seroprevalence suggests that pigs might serve as an important source of T. gondii infection for people. This is the first report of seroepidemiology of T. gondii infection in pigs in Ethiopia. Further studies are warranted for designing appropriate prevention and control strategies.

Latent Toxoplasma gondii Infection and Associated Risk Factors among HIV-Infected Individuals at Arba Minch Hospital, South Ethiopia

Toxoplasmosis is a parasitic disease caused by Toxoplasma gondii (T. gondii). The parasite has cosmopolitan distribution, infecting almost all species of warm-blooded animals. Latent T. gondii infection in HIV/AIDS patients is a risk for development of cerebral toxoplasmosis (CT). The aim of this study is to determine seroprevalence of latent T. gondii infection and assess its associated factors among individuals infected with HIV in Arba Minch Hospital, south Ethiopia. A facility-based cross-sectional study involving 170 HIV-infected individuals attending Arba Minch Hospital antiretroviral therapy (ART) clinic was conducted from April to June 2013. Data on demographic profile of the study participants and factors associated with T. gondii infection were gathered using a questionnaire. Serum was tested for IgG anti-T. gondii antibody by enzyme-linked immunosorbent assay (ELISA). Data were analyzed using SPSS version 20 software. Seroprevalence of latent T. gondii infection among the study participants was 88.2%. Consumption of raw meat (AOR = 4.361; 95% CI: 1.409-13.496) and involvement in farming/gardening activities (AOR = 4.051; 95% CI: 1.112-14.758) were independent predictors of T. gondii seropositivity. This study revealed high prevalence of latent T. gondii infection, similar to other studies. Monitoring of the patients to prevent reactivation of the latent T. gondii infection is recommended.

Genetic characterization of Toxoplasma gondii isolates and toxoplasmosis seroprevalence in stray cats of İzmir, Turkey

Currently, some Toxoplasma gondii genotypes are being associated with serious clinical presentations. A recent report showing the Africa 1 genotype in two local congenital toxoplasmosis cases acquired in Turkey formed the basis of this study because atypical Africa 1 genotype is most frequently detected in animals and patients from sub-Saharan Africa. Since stray cats are considered as the linkage between wild life and urban life in T. gondii transmission, the present study aimed to isolate and characterize T. gondii strains circulating in stray cats of İzmir (Western Turkey). A secondary objective was to determine toxoplasmosis seroprevalence in this cat population. Tissues obtained from 100 deceased stray cats were bioassayed and isolated strains were genotyped using 15 microsatellite markers. In addition, toxoplasmosis seroprevalence was analyzed in 1121 cat sera collected from several large veterinary clinics in İzmir. Among the 22 isolates, 19 were Type II (86.3%), two were Type III (9%) and one was Africa 1 genotype (4.5%). The overall seropositivity rates in cats were 42-48% and 33.4-34.4% according to IFA and ELISA, respectively. Seroprevalence in deceased cats was significantly higher than in healthy cats (P = 0.0033). Finding both the major clonal Type II lineage together with the Type III lineage also found in Middle East, and an atypical genotype, Africa 1 appears consistent with the specific geographic location of Turkey between three continents and raises the possibility of transportation of these strains between continents through trade routes or long distance migratory birds. In addition, the first large study of toxoplasma seroprevalence in a stray cat population was also reported. The relatively high seropositivity rates and the variety of T. gondii genotypes confirm the local stray cat population as a risk factor for human toxoplasmosis in İzmir.

Seroepidemiology ofToxoplasma gondiiinfection in free-range chickens (Gallus domesticus) of Central Ethiopia

We performed a seroepidemiological study ofToxoplasma gondiiinfection in free-range chickens from October 2012 to May 2013. We used cross-sectional two-stage cluster sampling to collect blood samples from wing veins of 601 chickens from central Ethiopia.T. gondii-specific antibodies were assayed by modified agglutination test (MAT). We collected information about risk factors by questionnaire and used univariable and multivariable logistic regression to assess risk factors. An overall seroprevalence of 30·5% [95% confidence interval (CI) 26·27–34·14] and 54·2% (95% CI 47·06–61·36) was found at animal- and flock-level, respectively. The MAT end titre of seropositive chickens (n = 183) were 1 : 60 in 46, 1 : 180 in 28, 1 : 540 in 29, ⩾1 : 1620 in 48, 1 : 6000 in 22, 1 : 18 000 in five, 1 : 54 000 in one, and ⩾1 : 162 000 in four. Animal-level risk factors identified using multivariable logistic regression model were: midland altitude [odds ratio (OR) 2·53, 95% CI 1·12–5·72], cross and exotic breeds (OR 3·17, 95% CI 1·39–7·23), increased age of chickens (OR 2·32, 95% CI 1·19–4·49), extensive management (OR 6·92, 95% CI 1·34–35·86) and the presence of cats (OR 2·08, 95% CI 1·20–3·61). Similarly, flock-level risk factors were midland altitude (OR 3·62, 95% CI 1·31–9·99) and the presence of cats (OR 1·19–4·94). The knowledge of the local people about the health risk of cats to humans and animals is poor. Housing and management of cats and chickens are also poor. The widespread presence ofT. gondiiinfection in free-range chickens of Central Ethiopia provides suggestive evidence for the high level of contamination of the living environment of people withT. gondiioocysts. Meat from free-range chickens might be an important source of infection for humans. Altitude, breed, age, management and presence of cats are independent predictors of seropositivity. Education of farmers about toxoplasmosis and further studies to elucidate the burden of toxoplasmosis in animals and humans warrants consideration.

High prevalence of Toxoplasma gondii oocyst shedding in stray and pet cats (Felis catus) in Virginia, United States

Background

The protozoan Toxoplasma gondii is the causative agent of toxoplasmosis, with complications varying from mental disease to death. While human infection can occur via ingestion of tissue cysts from infected meat, most human infection comes from oocysts. Cats are the only definitive host, and thus shedding of oocysts by cats provides the ultimate source of toxoplasmosis.

Methods

While most studies in the area use seroprevalence to monitor Toxoplasma incidence in cat populations, this provides only a history of infection. This study used PCR detection of oocysts from cat feces to more accurately estimate the numbers of cats producing oocysts and thus posing an active health risk. DNA sequencing was use to confirm the identity of the PCR products.

Results

Of the 49 cats tested, 9 yielded PCR products of the expected size. Six of the nine were determined by sequence analysis to be false positives, while three products were true positives. Overall, 6% of cats examined were found to be actively shedding oocysts.

Conclusions

The incidence of oocyst shedding in the cat population studied was significantly higher than expected and higher than found in most cat populations world-wide. Of equal importance, the primers tested were shown to produce PCR products of multiple sizes and non-target products of expected size. We detected false positives at a higher rate than true positives, emphasizing the need for confirmatory analysis. Further research may produce better protocols for Toxoplasma detection from cat fecal samples.

Genetic diversity of Toxoplasma gondii isolates from Ethiopian feral cats

Recent studies indicate greater genetic variability among isolates of Toxoplasma gondii worldwide than previously thought. However, there is no information on genetic diversity of T. gondii from any host in Ethiopia. In the present study, genotyping was performed on viable T. gondii isolates by bioassays in mice from tissues and feces of 27 cats from Ethiopia. Viable T. gondii was isolated from hearts of 26 cats, feces alone of 1 cat, and feces and tissues of 6 cats; in total there were 33 isolates. Genotyping was performed on DNA from cell-cultured derived T. gondii tachyzoites and by using 10 PCR-restriction fragment length polymorphism markers (SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico). Four genotypes were recognized, including ToxoDB #1 (Type II clonal, nine isolates), ToxoDB #2 (Type III, five isolates), Toxo DB #3 (Type II variant, ten isolates), and ToxoDB #20 (nine isolates). Of interest is the isolation of different genotypes from tissues and feces of two cats, suggesting re-infection or mixed strain T. gondii infection. These findings are of epidemiological significance with respect to shedding of oocysts by cats. This is the first report of genotyping of T. gondii from any host in Ethiopia.