Gondii Infection In Cats Research Articles

Comparison of the performance of SAG2, GRA6, and GRA7 for serological diagnosis of Toxoplasma gondii infection in cats.

Toxoplasmosis is an important zoonotic disease caused by Toxoplasma gondii that can infect almost all warm-blooded animals worldwide, including humans. The high prevalence of T. gondii infection and its ability to cause serious harm to humans and animals, especially immunodeficient individuals, make it a key public health issue. Accurate diagnostic tools with high sensitivity are needed for controlling T. gondii infection. In the current study, we compared the performance of recombinant SAG2, GRA6, and GRA7 in ELISA for the serological diagnosis of T. gondii infection in cats. We further investigated the antigenicity of recombinant dense granule protein 3 (rGRA3), rGRA5, rGRA8, and rSRS29A expressed in a plant-based, cell-free expression system for detecting antibodies in T. gondii-infected cats. In summary, our data suggest that GRA7 is more sensitive than the other two antigens for the serodiagnosis of T. gondii infection in cats, and GRA3 expressed in the cell-free system is also a priming antigen in serological tests for detecting T. gondii infection in cats.

Türkiye’nin Erzurum ilinde barınak kedilerinde Toxoplasma gondii enfeksiyonu için seroprevalans ve risk faktörleri

This study was aimed to evaluate the seroprevalence and risk factors of the infection of Toxoplasma gondii in cats kept in Animal Shelter and Rehabilitation Center of Erzurum Municipality in Erzurum that collected from stray. Total 70 blood samples were collected from apparently healthy cats and diseased cats such as diarrhea, and ocular and nasal discharge. Sera samples were stored in screw-capped sterile tubes at – 20 °C until analysis. In sera samples, IgG antibodies against T. gondii were analyzed by Sabin-Feldman Dye test. Of 70 cats, 25 (35.7%) was negative and 45 (64.3%) positive for T. gondii infection. An important association was not found between young and adult, female and male, and apparently healthy and diseased cats with T. gondii seropositivity. In this study, T. gondii seroprevalence was determined at high rates in cats kept in shelter in Erzurum provinceof Turkey. The prevention measures against T. gondii infection in cats should be implemented for animal and public health concerns.

Seroprevalence of and Risk Factors for Toxoplasma gondii Infection in Cats from Greece

Toxoplasmosis is one of the most important protozoan diseases with a global impact on the health of domestic cats and with zoonotic significance. The aims of this study were to determine the prevalence of seropositivity for Toxoplasma gondii in different populations of cats in Greece and to assess risk factors for seropositivity. A total of 457 cats were prospectively enrolled, and a commercially available indirect immunofluorescence antibody testing (IFAT) kit was used for the detection of anti-T. gondii immunoglobulin G (IgG) in serum. Overall, 95 (20.8%) of the 457 cats were seropositive for T. gondii. Based on multivariate analysis, factors associated with seropositivity included older age [Odds ratio (OR), 1.33; p < 0.001]; a history of cat-fight trauma (OR, 3.88; p = 0.004); and lack of vaccination against calicivirus, herpesvirus-1, panleukopenia, and rabies (OR, 10; p = 0.002). This study shows a high prevalence of seropositivity for T. gondii in cats in Greece. This implies that toxoplasmosis is still a major public health concern and that optimal strategies for the prevention of infection with T. gondii in cats should be established.

Seroprevalence and risk factors of Toxoplasma gondii in urban cats from China

BackgroundToxoplasma gondii infects almost all warm-blooded animals, and cats play a crucial role in the epidemiology of T. gondii as the definitive host. Despite sporadic reports on the seroprevalence of T. gondii in domestic cats, systematic surveys are lacking and some regions remain in China uninvestigated.MethodsA total of 1,521 serum samples were collected from 10 regions of China and analyzed by antibodies against T. gondii by ELISA with the purpose of identifying risk factors of T. gondii infection in cats across China and obtaining seroprevalence data from some previously uninvestigated areas.ResultsAntibodies to T. gondii were detected in 62 of 1,478 (4.2%) urban pet cats and in 9 of 43 (20.9%) stray cats. Among the regions examined, the prevalence was 13% in Sichuan, 12.8% in Chongqing, 6.4% in Hunan, 2.5% in Hubei and 0.9% in Guangdong. Additionally, this is the first report on the seroprevalence of T. gondii in urban pet cats from Qinghai (6.2%), Anhui (3.1%), Jiangxi (2.5%), Shaanxi (2.4%) and Ningxia (1.6%). The age and lifestyle (stray or pet) of cats were identified as the risk factors for seropositivity by multivariate analysis of the data.ConclusionsOur findings improve our understanding of seroprevalence and risk factors of T. gondii infection in cats across China, and provide useful information for the formulating of preventive and control measures against this widespread zoonotic parasite.

Cats Toxoplasmosis Control in Indonesia

Toxoplasmosis is one of the parasitic diseases caused by Toxoplasma gondii (T. gondii). Toxoplasma gondii is usually found in cats’ faeces, raw vegetables, meats, grasses, and soil. The transmission of T. gondii happens vertically or horizontally. The standard diagnostic techniques of T. gondii detection are microscopic examination of cats faeces, PCR, and antibody detection. The drug of choice in cats toxoplasmosis is clindamycin antibiotic (doses: 10-12/kgBW), another treatment is the combination of sulfadiazine 120 mg/kgBW dan pirimetamin 1 mg/kgBW also can be given to reduce the oocyst shed. The prevention of T. gondii infection in cats is not giving raw meats and keeping the environment disinfected. The prevalence of cats toxoplasmosis in cats in Indonesia is influenced by multiple diagnostic techniques, sample total, geographical condition, and climate. The risk factor of toxoplasmosis infection in cats are stray cats, raw foods, and a hygienic environment. The purpose of this article is knowing the life cycle of T. gondii, clinical sign, pathogeneses, diagnostic method, risk factors, control, and the prevalence of cats toxoplasmosis in Indonesia in the last 50 years.

Serological survey of Toxoplasma gondii infection in cats in Khon Kaen, Northeast Thailand.

Background and Aim:Toxoplasmosis is a zoonosis caused by Toxoplasma gondii. Cats are known to be the definitive hosts that can excrete these environmentally resistant oocysts. Other mammals, avians, and even humans can serve as the intermediate host. T. gondii infection is often asymptomatic in healthy individuals; however, it could result in serious health problems in immunocompromised and pregnant individuals. This study investigated the occurrence of T. gondii infection in cats in Khao Suan Kwang and Mueang Khon Kaen.Materials and Methods:In total, 100 serum samples from cats, that is, 62 owned cats (31 males and 31 females) and 38 adopted stray cats (21 males and 17 females), were examined for antibodies against T. gondii through rapid immunochromatographic tests (ICT). Owners were asked to sign a consent form and answer the questionnaires before sample collection. Demographic information about the cats and their owners was also recorded.Results:The overall seroprevalence of cats positive for T. gondii antibodies was found to be 5%. Notably, the Toxoplasma antibody prevalence was significantly higher in the adopted stray cats (10.53% [4/38]) that roamed the zoo than in the owned cats (1.61% [1/62]) (p > 0.05). No significant difference was observed between male (8.33%) and female (1.92%) cats. The cat owners’ questionnaire revealed that more than half had never heard of toxoplasmosis before (67.7%), whereas 30.6% knew nothing about the disease transmission routes.Conclusion:This study presented a low seroprevalence of antibodies to T. gondii in owned cats from the Mueang Khon Kaen District, whereas high seroprevalence was detected in the adopted stray cats from Khao Suan Kwang. Adopted stray cats can have a higher potential for T. gondii infection; thus, they could be a source of toxoplasmosis transmission to humans. Therefore, it is essential to control the number of stray cats, and a screening test for antitoxoplasmosis could be recommended before adoption. Although the total seroprevalence was noted to be low, the zoonotic disease was present. Therefore, raising the community’s awareness and knowledge might reduce the disease transmission from animals to humans.

Comparative performance of five recombinant and chimeric antigens in a time-resolved fluorescence immunoassay for detection of Toxoplasma gondii infection in cats

Felids are definitive hosts of Toxoplasma gondii, being the only hosts that can spread the infection through oocyst shedding in their feces. The elevated presence of this parasite in the domestic cat (Felis catus), and its close contact with humans, make it necessary to obtain reliable diagnostic methods to detect positive animals as a public health measure. For this reason, in this study, the diagnostic performance of five different recombinant antigen-based techniques was assessed to diagnose T. gondii infection in cat blood plasma samples. Specifically, four T. gondii recombinant antigens (GRA7, truncated GRA7, SAG2, and truncated SAG2) and a chimeric antigen (SAG1-GRA8) were used. A time-resolved fluorescence immunoassay (TRFIA) was developed for each antigen, and the results of each of these techniques were compared with those obtained by a commercial enzyme-linked immunoassay (ELISA) and a modified agglutination test (MAT) as reference techniques. The TRFIA based on SAG1-GRA8 antigen showed better discrimination between seropositive and seronegative cats (p < 0.001), as well as a better area under the curve (0.95), sensitivity (93.6%), and specificity (89.5%) values for the optimal cut-off, versus the other TRFIAs. In addition, SAG1-GRA8 TRFIA showed substantial agreement (kappa value = 0.78) and a moderate significant correlation (Spearman’s correlation: r = 0.62, p < 0.001) compared with the reference techniques. On the other hand, since plasma samples were obtained from 101 cats in Bangkok city and four of them were Neospora caninum seropositive by indirect immunofluorescence assay (IFAT), this is the first time that anti-N. caninum antibodies are detected in cats in Thailand. In conclusion, our study highlights that the TRFIA with TgSAG1-GRA8 antigen is an accurate and recommended diagnostic technique for detecting anti-T. gondii antibodies in cats.

Development and evaluation of indirect enzyme-linked immunosorbent assay using recombinant dense granule antigen 7 protein for the detection of Toxoplasma gondii infection in cats in Thailand.

Background and Aim:Toxoplasma gondii is recognized as a zoonosis causing toxoplasmosis in animals globally. Cat is a definitive host of T. gondii and sheds oocyst through feces, which can infect human beings and animals through contaminated food ingestion. A precise diagnostic test is essential to prevent T. gondii infection in both humans and animals. This study aimed to develop and evaluate the pETite-dense granule antigen 7(GRA7)-based indirect enzyme-linked immunosorbent assay (ELISA) to detect T. gondii infection in cats.Materials and Methods:T. gondii-GRA7 was cloned and expressed in the Expresso®small ubiquitin-related modifier (SUMO) T7 Cloning and Expression System. The recombinant pETite-GRA7 was purified using HisTrap affinity chromatography and confirmed using Western blot analysis. The recombinant protein was used to develop and evaluate the indirect ELISA for T. gondii infection detection. In total, 200 cat sera were tested using pETite-GRA7-based indirect ELISA and indirect fluorescent antibody test (IFAT). The statistical analysis based on Kappa value, sensitivity, specificity, positive predictive value, negative predictive value, χ2 test, and receiver operating characteristic (ROC) curve was used to evaluate the performance of the test.Results:A 606 bp GRA7 polymerase chain reaction (PCR) product was obtained from T. gondii RH strain genomic DNA. The gene was cloned into the pETite™ vector and transformed to HI-Control Escherichia coli BL21 (DE3) for protein expression. Approximately 35 kDa of recombinant pETite-GRA7 was observed and Western blot analysis showed positive bands against anti-6-His antibody and positive-T. gondii cat serum. A sample of 0.5 μg/mL of pETite-GRA7 was subjected to indirect ELISA to detect T. gondii infection in the cat sera. The results showed sensitivity and specificity of pETite-GRA7-based indirect ELISA at 72% and 96%, respectively. An acceptable diagnostic performance was characterized by high concordant results (94%) and substantial agreement (Kappa value=0.65) with IFAT. The seroprevalence levels of ELISA and IFAT were 10% and 9%, respectively, and were not significantly (p>0.05) different. The expected performance of ELISA at different cutoff points using the ROC curve analysis revealed 89% sensitivity and 92% specificity at the cutoff value of 0.146, with a high overall assay accuracy (area under the curve=0.94).Conclusion:In this study, the pETite™ vector, N-terminal 6xHis SUMO fusion tag, was used to improve the solubility and expression level of GRA7. The recombinant pETite-GRA7 showed enhanced protein solubility and purification without special condition requirements. This pETite-GRA7-based indirect ELISA showed high concordant results and substantial agreement with IFAT. ELISA revealed an acceptable sensitivity and specificity. These initial data obtained from cats’ sera demonstrated that pETite-GRA7-based indirect ELISA could be a useful method for local serological diagnosis of T. gondii infection in cats in Thailand.

Prevalence of Toxoplasma gondii Measured by Western Blot, ELISA and DNA Analysis, by PCR, in Cats of Western Mexico.

Toxoplasma gondii is the causative agent of toxoplasmosis in humans and animals. The sexual reproductive cycle of Toxoplasma takes place in the small intestine of felines, the definitive hosts. In the final part of the sexual cycle, T. gondii forms oocysts in infected cats. Oocysts transferred via the faeces to the environment are highly infectious to both animals and humans. This study aimed to determine the prevalence and risk factors associated with T. gondii infection in cats from the metropolitan region of Guadalajara in western Mexico. Western blotting and ELISA for anti-Toxoplasma IgG antibodies was performed, and Toxoplasma DNA was identified using polymerase chain reaction. Prevalence of anti-T. gondii antibodies was 14.8% (44/297), and only 2/297 cases were positive for PCR. Cats older than one year were at an increased risk of infection (OR = 3.9, 95% CI 1.844–8.362). Sex, raw meat feeding, hunting habits, vaccination status, and body condition were not associated with positivity. The prevalence of T. gondii infection determined with Western blot in cats in the metropolitan area of Guadalajara, Jalisco, Mexico, was lower than that reported in previous studies.

Prevalence of toxoplasmosis in semi-domesticated and pet cats within and around Bangkok, Thailand

BackgroundToxoplasmosis is one of the most common parasitic zoonoses worldwide. Cats become infected after ingesting infected tissue cysts. The objective of the present study was to compare the prevalence of toxoplasmosis in pet cats and semi-domesticated cats in the Bangkok metropolitan region. A survey of Toxoplasma infection was conducted in 260 cats (median age [range]: 3 years [10 months–10 years]; 155 females and 105 males) by collecting blood samples from 130 client-owned pet cats and 130 semi-domesticated cats within and around Bangkok during 2016–2017 using indirect fluorescence antibody tests. An IgG antibody to Toxoplasma antigen ratio of ≥1:100 was considered positive for Toxoplasma infection.ResultsThe overall prevalence of T. gondii in cats was 6.5% (17/260). The prevalence of T. gondii in semi-domesticated cats and pet cats was 11.5 and 1.5%, respectively. Semi-domesticated cats aged 1–5 years (14.9%) had a higher prevalence of infection than domesticated cats (1.3%, p = 0.002) of the same age. The odds (95% confidence interval [CI]) of having T. gondii infection in semi-domesticated cats were 8.34 (1.86–76.29, p = 0.0017) times higher than in pet cats. Interestingly, there was an association between T. gondii infection according to city ​region (p = 0.002). The odds (95% CI) of having T. gondii infection in cats living in the inner city were 4.96 (1.03–47.16, p = 0.023) times higher than cats living in the suburb and the vicinity.ConclusionsThe present study identified a higher prevalence of Toxoplasma infection in semi-domesticated cats compared with pet cats. The semi-domesticated cats could serve as a zoonotic reservoir. Public health regulations should be implemented to prevent toxoplasmosis spread.

Comparison of the modified agglutination test and real-time PCR for detection of Toxoplasma gondii exposure in feral cats from Phillip Island, Australia, and risk factors associated with infection.

Toxoplasma gondii is considered a disease risk for many native Australian species. Feral cats are the key definitive host of T. gondii in Australia and therefore, investigating the epidemiology of T. gondii in cat populations is essential to understanding the risk posed to wildlife. Test sensitivity and specificity are poorly defined for diagnostic tests targeting T. gondii in cats and there is a need for validated techniques. This study focused on the feral cat population on Phillip Island, Victoria, Australia. We compared a novel real-time PCR (qPCR) protocol to the modified agglutination test (MAT) and used a Bayesian latent class modelling approach to assess the diagnostic parameters of each assay and estimate the true prevalence of T. gondii in feral cats. In addition, we performed multivariable logistic regression to determine risk factors associated with T. gondii infection in cats. Overall T. gondii prevalence by qPCR and MAT was 79.5% (95% confidence interval 72.6–85.0) and 91.8% (84.6–95.8), respectively. Bayesian modelling estimated the sensitivity and specificity of the MAT as 96.2% (95% credible interval 91.8–98.8) and 82.1% (64.9–93.6), and qPCR as 90.1% (83.6–95.5) and 96.0% (82.1–99.8), respectively. True prevalence of T. gondii infection in feral cats on Phillip Island was estimated as 90.3% (83.2–95.1). Multivariable logistic regression analysis indicated that T. gondii infection was positively associated with weight and this effect was modified by season. Cats trapped in winter had a high probability of infection, regardless of weight. The present study suggests qPCR applied to tissue is a highly sensitive, specific and logistically feasible tool for T. gondii testing in feral cat populations. Additionally, T. gondii infection is highly prevalent in feral cats on Phillip Island, which may have significant impacts on endemic and introduced marsupial populations.

Toxoplasma gondii Seropositivity and Associated Risk Factors in Cats (Felis catus) in Three Provinces in Northeastern China from 2013 to 2019.

Toxoplasma gondii is an important protozoan parasite that can infect a range of animals. Cats are the most important definitive hosts for T. gondii. Therefore, an assessment of the level of T. gondii infection in cats is of public health importance. As limited information about seroprevalence of T. gondii infection in cats in northeastern China was available, 854 serum samples, including 235 cats in Jilin province, 267 cats in Liaoning province, and 352 cats in Heilongjiang province, were examined by an indirect hemagglutination assay (IHA) test, between September 2013 and July 2019. The overall seroprevalence of T. gondii was 19.09% (163/854) at the cutoff 1:64, with 19.60% (69/352), 18.29% (43/235), and 19.10% (51/267) in Heilongjiang, Jilin and Liaoning, respectively. Logistic regression analysis showed that mode of life was highly related to T. gondii infection in cats at the investigation areas. These results could provide foundation data for prevention and control of T. gondii prevalence in these regions. Moreover, the results also suggested that the effective control strategies should continue to be performed.

Detection of antibodies against Toxoplasma gondii in cats using an immunochromatographic test based on GRA7 antigen.

Toxoplasmosis, caused by Toxoplasma gondii, is one of the most common parasitic diseases worldwide. The GRA7 of T. gondii (TgGRA7) is an essential component of the parasitophorous vacuole (PV) and PV membrane surrounding the tachyzoites and the cyst wall of the bradyzoites. While it has been widely employed as antigen for ELISA, there is only one study that has reported its potential as antigen for immunochromatographic test (ICT) in pigs. There is no study yet documenting its potential for ICT serodiagnosis of T. gondii infection in cats. In this study, we assessed the efficacy of an ICT using TgGRA7 in the detection of Toxoplasma infections in 100 cats and compared the results with iELISAs using TgGRA7 and lysate antigens of T. gondii strains, RH, PLK, and VEG. Our results revealed that TgGRA7-ICT is a reliable test for the diagnosis of anti-T. gondii antibodies in cats, producing comparable results as conventional serological methods. This study is the first report on the use of TgGRA7 as ICT antigen for the serodiagnosis of T. gondii infection in cats.

Development and evaluation of an enzyme-linked immunosorbent assay based on recombinant TgSRS2 for serodiagnosis of Toxoplasma gondii infection in cats.

An enzyme-linked immunosorbent assay (ELISA) based on recombinant SAG1-related sequence 2 of Toxoplasma gondii (rTgSRS2) was developed to detect toxoplasmosis in cats. The specificity and sensitivity of rTgSRS2 ELISA were confirmed using a series of serum samples from T. gondii-experimentally infected mice. A total of 76 field samples from cats were examined by the developed ELISA. The rTgSRS2 ELISA showed a good diagnostic performance characterized by high concordance (88.16) and kappa value (0.76) with latex agglutination test (LAT). The sensitivity and specificity of the test were 92.68% and 82.86%, respectively. These results suggest that the ELISA based on rTgSRS2 could be a useful tool for serodiagnosis of T. gondii infection in cats.

Toxoplasmosis in Cats and Its Zoonotic Potential in and Around Bangladesh Agricultural University Campus

Toxoplasmosis is a zoonotic disease, occurs in almost all warm blooded animals including human beings and is caused by a global protozoan intracellular parasite Toxoplasma gondii. It is estimated that one third of the world human population have been infected by this parasite. This protozoan causes a significant public health problem in humans and imposes considerable economic losses and damages to livestock. The final host is cat, Feliscatus, accounts for all of these significant burdens. Hence the present study was designed to determine the prevalence rate of T. gondii infection in cats and also to analyze the associated factors that were potential for human beings and livestock as well in the period from September 2014 to August 2016. Altogether 254 faecal samples from cat and 390 water samples were collected from Bangladesh Agricultural University (BAU) campus, farm and residential areas of BAU and were examined for presence of T. gondii oocysts at Department of Parasitology, BAU Mymensingh. The overall prevalence of T. gondii was 4.03% (26/644). Presence of T. gondii oocysts in faecal and water samples were 5.5% (14/254) and 3.08% (12/390), respectively. Adult cats had higher (6.7%) prevalence than young cats (3.8%). Summer season was found high prevalence (6.7%) of oocysts in cat faeces. Similarly drain water found higher positivity (6.67%) of oocysts. Therefore, this study concluded that the cats are contaminating the environment by shedding oocysts and then other animals can get the infection from grazing of contaminated grasses and drinking water. So eating undercooked goat, sheep and cattle meat; eating contaminated vegetables and drinking contaminated water are major sources for getting toxoplasmosis to human beings. Hence this disease has great zoonotic importance around BAU campus and therefore it is essential to create public awareness.&#x0D;

Seroprevalence and associated risk factors of Toxoplasma gondii infection in domestic animals in southeastern South Africa

Toxoplasma gondii is a major neglected parasitic infection occurring in settings of extreme poverty in Africa. Apart from causing reproductive failure in animals it is also a significant zoonotic concern. The objective of this study was to determine the seroprevalence and associated risk factors of T. gondii infection in cats, chickens, goats, sheep and pigs in the southeast of South Africa, of which little is known. Sera was obtained from 601 domestic animals including 109 cats, 137 chickens, 128 goats, 121 sheep and 106 pigs managed under different production systems in different agro-ecological regions and evaluated by the Toxoreagent, a latex agglutination test for T. gondii antibody detection. Household-level and animal-level data were collected by interviewing animal owners and/or herders using a closed-ended questionnaire. The study revealed an overall farm seroprevalence of 83.33% (125/150 farms) with the highest rate of infection for the parasite found in sheep with 64.46% (78/121), followed by goats with 53.91% (69/128), pigs with 33.96% (36/106), cats with 32.11% (35/109 cats) and chickens with 33.58% (46/137). The risk factors that were found to be statistically significant (p < 0.05) to different species of seropositivites were age, location, climate, animal production system, rodent control, seropositive cat, cat-feed access and cat faecal disposal. The relatively high seroprevalence of T. gondii detected in this region suggests that domestic animals may pose a substantial public health risk through the consumption of T. gondii-infected raw meat as well as via contact with cat faeces.

Acute Toxoplasma Gondii Infection in Cats Induced Tissue-Specific Transcriptional Response Dominated by Immune Signatures.

RNA-sequencing was used to detect transcriptional changes in six tissues of cats, seven days after T. gondii infection. A total of 737 genes were differentially expressed (DEGs), of which 410 were up-regulated and 327 were down-regulated. The liver exhibited 151 DEGs, lung (149 DEGs), small intestine (130 DEGs), heart (123 DEGs), brain (104 DEGs), and spleen (80 DEGs)-suggesting tissue-specific transcriptional patterns. Gene ontology and KEGG analyses identified DEGs enriched in immune pathways, such as cytokine-cytokine receptor interaction, Jak-STAT signaling pathway, NOD-like receptor signaling pathway, NF-kappa B signaling pathway, MAPK signaling pathway, T cell receptor signaling pathway, and the cytosolic DNA sensing pathway. C-X-C motif chemokine 10 (CXCL10) was involved in most of the immune-related pathways. PI3K/Akt expression was down-regulated in all tissues, except the spleen. The genes for phosphatase, indoleamine 2,3-dioxygenase, Hes Family BHLH Transcription Factor 1, and guanylate-binding protein 5, playing various roles in immune defense, were co-expressed across various feline tissues. Multivariate K-means clustering analysis produced seven gene clusters featuring similar gene expression patterns specific to individual tissues, with lung tissue cluster having the largest number of DEGs. These findings suggest the presence of a broad immune defense mechanism across various tissues in cats against acute T. gondii infection.

Prevalence of Toxoplasma gondii infection in cats in southwestern Poland.

An assessment of the prevalence of Toxoplasma gondii infection in cats from southwestern Poland using serology, coproscopy and PCR methods. In total, 208 cats (139 females and 68 males), aged 0.5-12 years (mean=2.6) from 25 localities in southwestern Poland were examined by indirect immunofluorescence assay (IFAT) to estimate the T. gondii serological status. Faecal samples of 41 cats were examined for the presence of oocysts/DNA T. gondii by microscopy and Real-time/nested PCR. After flotation (with NaNO3), pellets from faecal samples were disrupted by 10 cycles of freezing (liquid nitrogen) and warming. DNA was extracted using QIamp DNA Stool Mini Kit (Qiagen), according to the manufacturer's instruction. The positive results in IFAT for anti-T. gondii IgG and IgM antibodies were found in 143 of 208 tested cats (68.8%). Among positive results, 14.5%, 34.1% and 51.4% were detected in titre ranges 128-512, 1,000-2,000 and ≥ 4,000, respectively. In 23.1% of cat sera anti-T. gondii IgM antibodies were found. The prevalence of anti-Toxoplasma antibodies was significantly greater in older cats (>1 year) (83.5%) than in younger cats (48.3%) (P<0.05), in females (74.1%) than in males (58.8%) (P<0.05), and in cats kept outdoors than indoors (69.7% vs. 16.7%) (P<0.01). Among the 41 faecal samples examined, the presence of structures resembling T. gondii oocysts was found in 2 samples (4.9%), and for one of these samples (2.4% of the total) the result was also confirmed by PCR. T. gondii infection in domestic cats is highly prevalent in southwestern Poland. Information on the prevalence of infection in cats can be useful for assessing T. gondii environmental contamination and the risk for public health.

Schizogony and gametogony of oocyst-deficient T-263 strain of Toxoplasma gondii

Oocysts are important stage for the spread of Toxoplasma gondii because they are environmentally resistant. Among all hosts of T. gondii, only felids can excrete oocysts. Cats that have excreted T. gondii oocysts after primary infection develop immunity to re-excretion of oocysts, and this immunity appears to be long-lasting. It would be desirable to have a non-infectious vaccine for the prevention of T. gondii infection in cats and to understand mechanism of immunity to excretion of oocysts. An initial step will be to indentify stage/stages of the parasite for induction of immunity. A chemically-induced mutant of T. gondii, T-263, is immunogenic but lacks the capacity to form oocysts in cats. Cats fed live bradyzoites of T-263 do not excrete oocysts after challenge with oocyst producing strains. However, it is not known at what stage of the parasite development the oocyst formation is halted. Here, four cats were fed live tissue cysts of the T-263 strain and examined for enteroepithelial stages and oocyst production. Two cats were administered methyl prednisolone aceatate (20mg/kg) once intramuscularly and these cats were euthanized 5 and 7days post inoculation. No oocysts but immature and mature schizonts (types D and E), male, and female gamonts were detected in two cats euthanized. The remaining two cats did not excrete oocysts examined 3–14days post inoculation, but both seroconverted and developed antibody titers of 1:400 tested by the modification agglutination test, indicating exposure to the inocula. The results demonstrate that the T-263 strain is defective in oocyst formation and the observations should help future studies in identification of genes/factors responsible for oocyst formation in the intestine of cats.

Serologic survey of Toxoplasma gondii antibodies in cats (Felis catus) sold at live animal markets in Southwestern Nigeria

Toxoplasma gondii is a zoonotic parasite causing infection in humans and a wide range of mammals, with cats being the final and only host that excrete T. gondii-resistant oocysts to the environment. This study was designed to investigate the seroprevalence of antibodies to T. gondii in cats sold at Live Animal Markets (LAMs) in Ibadan, Osogbo and Offa, Southwestern Nigeria. Blood samples were randomly collected from 226 cats at these markets and separated sera were tested for the presence of antibodies (IgG) to T. gondii, using two-fold dilutions from 1:20 to 1:320 by the Modified Agglutination Test (MAT). Attributes were analysed using Chi-square and Fisher’s exact tests at P<0.05. Median age of cats was 4.0 months (range: 1–36 months). Of the 226 samples tested, only 10 (4.4%) were positive for anti-T. gondii IgG antibodies at the cut-off titre of 1:20. Nine (4.0%) gave a titre of 1:20; one (0.4%) gave 1:80 while none was positive at 1:40, 1:160 and 1:320 dilutions. Age and gender of cats was not significantly associated with T. gondii infection. Our results showed low prevalence of T. gondii infection in cats sold at LAMs in studied area and suggests confinement as an efficient way of limiting exposure of cats to infection sources.