Seroprevalence of Toxoplasma gondii antibodies in free-ranging mithuns (Bos frontalis) from India

Studies conducted on free-ranging mithuns of Nagaland, India revealed that the overall seroprevalence of antibodies to Toxoplasma gondii in mithun was 42% (95% CI = 33-51) when detected by modified direct agglutination test. Highest (prevalence = 57%, 95% CI = 43-71) seroprevalence was found in mithuns above 3 years of age and the lowest (prevalence = 18%, 95% CI =4-32) in mithuns of 1-2 years old. No statistically significant difference was observed between male (prevalence = 40%, 95% CI = 26-54) and female (prevalence = 44%, 95% CI = 31-57) seroprevalences. The study also revealed that the maximum number (57%) of animals with the highest titre (1 : 3200) were above 3 years of age. This is the first serological survey for Toxoplasma gondii antibodies in free-ranging mithuns from India.     

Seroprevalence of brucellosis in mithuns (Bos frontalis) in India

Studies conducted on the seroprevalence of brucellosis in 98 mithuns maintained at the National Research Centre on Mithun, Nagaland, India revealed that the number of animals found positive for brucellosis in avidin-biotin enzyme-linked-immunosorbent assay, standard tube-agglutination test and Rose-Bengal plate test were 34, 20 and 11%, respectively. Highest prevalence of brucellosis was observed in the Mizoram mithun strain. The relative sensitivity and specificity of the standard tube-agglutination test were 61 and 100%, respectively; the corresponding values of the Rose-Bengal plate test were 33 and 100%, respectively.     

Prevalence of Cryptosporidium parvum in mithuns (Bos frontalis) from India

Systematic examination of faecal samples from mithuns maintained at the National Research Centre on Mithun, Indian Council of Agricultural Research (ICAR), Nagaland, India and mithuns found in free-ranging condition of Nagaland, by using a commercially available enzyme-linked immunosorbent assay kit, revealed that the overall prevalence of Cryptosporidium parvum in mithun was 56% (95% CI=48-64). Highest (prevalence rate=81, 95% CI=67-95) prevalence was found in mithuns of 1-6 months of age and lowest (prevalence rate=42, 95% CI=31-53) in mithuns above 2 years of age. The prevalence was found to be higher (94%) in diarrhoeic animals in comparison to non-diarrhoeic group (51%). No statistically significant difference was observed between male (prevalence rate=61, 95% CI=48-74) and female (prevalence rate=53, 95% CI=43-63) prevalences. The prevalence was found to be higher (prevalence rate=64, 95% CI=55-73) in mithuns kept in semi-intensive system than mithuns found in free-ranging condition (prevalence rate=40, 95% CI=27-53). The risk factor that may play a pivotal role in the epidemiology of cryptosporidiosis in mithun is also discussed in brief. The zoonotic implication of the disease is also discussed. This is probably the first report on prevalence of Cryptosporidium parvum in mithun.     

Seroprevalence of Toxoplasma gondii antibodies in captive elephants (Elephaus maximus maximus) in Sri Lanka

Serum samples collected during August 2003-June 2004 from 45 privately owned captive and 8 elephants from the Pinnawala Elephant Orphanage were tested for the presence of antibodies against Toxoplasma gondii using the direct modified agglutination test (MAT). Antibodies were found in sera of 14 of 45 (32%) privately owned elephants with titers of 1:25 in three, 1:50 in three, 1:100 in three, 1:200 in three, and 1:400 in three elephants. The elephants from Pinnawala Elephant Orphanage were seronegative. This is the first report of T. gondii seroprevalence in elephants in Sri Lanka.     

Seroprevalence of Toxoplasma gondii in captive neotropical felids from Brazil.

Seroprevalence of Toxoplasma gondii was determined in 865 captive neotropical felids from 20 states from Brazil, sampled from September 1995 to April 1997. Sera were tested by the modified agglutination test (MAT) using formalin-fixed whole tachyzoites and mercaptoethanol. Antibodies (MAT> or =1:20) to T. gondii were found in 472 of 865 (54.6%) cats: in 45 of 99 (45.9%) jaguarundis (Herpailurus yagouaroundi), in 97 of 168 (57.7%) ocelots (Leopardus pardalis), in 68 of 131 (51.9%) oncillas (L. tigrinus), in 35 of 63 (55.5%) margays (L. wiedii), in 1 of 8 (12.5%) Pampas-cat (Oncifelis colocolo), in 9 of 12 (75.0%) Geoffroys-cat (O. geoffroyi), in 134 of 212 (63.2%) jaguars (Panthera onca), and in 83 of 172 (48.2%) pumas (Puma concolor). Antibody titers were: 1:20 in 27 felids, 1:25 in 142 felids, 1:40 in 6 felids, 1:50 in 292 felids, and > or =1:500 in 5 felids. The high seroprevalence of T. gondii antibodies found in the present study suggested a widespread exposure of neotropical cats to T. gondii in zoos in Brazil. The results warrant an investigation on the mode of exposure and oocyst shedding by neotropical cats.     

Seroprevalence of Toxoplasma gondii in captive felids in Thailand

The prevalence of antibodies against Toxoplasma gondii was investigated by commercial latex agglutination test kit (Toxocheck-MT 'Eiken') in captive felids maintained at zoos and a wildlife breeding center in different geographic regions of Thailand. Sera from a total of 136 captive felids of 12 species was obtained between 2002 and 2004. The overall seroprevalence of T. gondii was found in 21 of 136 (15.4%) felids. The titers varied from 1:64 (eight samples) to 1:8192 (one sample). The seroprevalence in different geographic regions were from 0% in the northern area to 23% in the southern area. This study suggested a widespread exposure of captive felids to T. gondii in Thailand and this is the first report of serologic analysis for T. gondii in captive felids in Southeast Asia.     

Seroprevalence of Toxoplasma gondii antibodies from wild canids from Brazil

The prevalence of anti-Toxoplasma gondii antibodies was evaluated by the indirect immunofluorescent-antibody test in serum of 57 wild canids from three different species: Lycalopex gymnocercus, Cerdocyon thous and Dusicyon vetulus from the northeast, southeast and southern regions of Brazil. The prevalence was 35.1%, with 20 of the 57 canids demonstrating antibodies anti-T. gondii at dilutions of 1:16 in 2, 1:32 in 4, 1:64 in 2, 1:128 in 2, 1:256 in 6, 1:512 in 2 and 1:2048 in 2 animals. None of the D. vetulus were positive. Among the L. gymnocercus 11 (91.7%) of the 12 samples were positive and among C. thous 9 (60%) of the 15 had antibodies anti-T. gondii.     

Seroprevalence of Toxoplasma gondii antibodies in wild carnivores from Spain

Serum samples from 282 wild carnivores from different regions of Spain were tested for antibodies to Toxoplasma gondii by the modified agglutination test using a cut-off value of 1:25. Antibodies to T. gondii were found in 22 of 27 (81.5%) of Iberian lynx (Lynx pardinus), 3 of 6 European wildcats (Felis silvestris), 66 of 102 (64.7%) red foxes (Vulpes vulpes), 15 of 32 (46.9%) wolves (Canis lupus), 26 of 37 (70.3%) Eurasian badgers (Meles meles), 17 of 20 (85.0%) stone martens (Martes foina), 4 of 4 pine martens (Martes martes), 6 of 6 Eurasian otters (Lutra lutra), 4 of 4 polecats (Mustela putorius), 1 of 1 ferret (Mustela putorius furo), 13 of 21 (61.9%) European genets (Genetta genetta), and 13 of 22 (59.1%) Egyptian mongooses (Herpestes ichneumon). Serological results indicated a widespread exposure to T. gondii among wild carnivores in Spain. The high T. gondii seroprevalence in Iberian lynx and the European wildcat reported here may be of epidemiologic significance because seropositive cats might have shed oocysts.     

Seroprevalence of Toxoplasma gondii in American free-ranging or captive pumas (Felis concolor) and bobcats (Lynx rufus)

Toxoplasma gondii is a major zoonotic agent infecting a wide range of mammals, including wild felids. Like domestic cats, wild felids are involved in the complete infective cycle of T. gondii, as they can host in their gastrointestinal tract sexually mature parasites and shed infective oocysts in their feces. In order to evaluate the importance of this wildlife reservoir, 438 serum samples collected between 1984 and 1999 from 438 pumas (Felis concolor) and from 58 bobcats (Lynx rufus) from North America, Central America and South America were screened for antibodies to T. gondii. The overall prevalence of T. gondii antibodies was 22.4% in pumas and 51.7% in bobcats, with regional variations. Adults were more likely to be seropositive than juveniles and kittens (prevalence ratio (PR) = 2.61; confidence interval (CI) = 1.15, 4.04). In the US, pumas from the southwestern states (Arizona, California and New Mexico) were more likely to be seropositive for T. gondii ( PR = 2.61; 95% CI = 1.32-5.18 ) than pumas from the northwestern and mountain states (Colorado, Idaho, Oregon, Utah and Wyoming). Male pumas from the US were more likely to be seropositive than females (PR = 2.08; 95% CI = 1.11-3.92), whereas female pumas from Mexico, Central America and South America were more likely to be seropositive than female pumas from Canada and the US (PR = 2.49; 95% CI = 1.09-5.69). Captive pumas were also more likely to be seropositive (21.7%, 29/92) for T. gondii than free-ranging animals (19.9%, 69/346) (PR = 1.85; 95% CI = 1.06, 3.17).     

Seroprevalence of Toxoplasma gondii in wild pigs (Sus scrofa) from Spain

Sera collected from 507 hunter-killed wild pigs (Sus scrofa) between 1993 and 2004 from five geographic regions in northern Spain and seven regions in southern Spain were assayed for antibodies to Toxoplasma gondii by the modified agglutination test (MAT). Antibodies to T. gondii were detected in 185 (38.4%) of 507 pigs with titers of 1:25 in 71, 1:50 in 111 and > or =1:500 in 3; seroprevalence was significantly higher (P<0.05) in pigs from southern regions. Seroprevalence was density dependent; it was higher in pigs from high stocking per hectare and availability of forage. Statistically significant differences were not observed between T. gondii seroprevalence and hunting estates (open versus fenced), sex or age. Serological results indicate a widespread exposure to T. gondii among Spanish wild boars, suggesting that this population could represent a public health risk for persons that handle or consume raw or undercooked infected wild pig meat.     

Serological evidence of Neospora caninum infection in mithun (Bos frontalis) from India

Studies conducted on mithuns maintained at National Research Centre on mithun, Indian Council of Agricultural Research (ICAR), Nagaland, India and mithuns found in free-ranging condition of Nagaland revealed that the overall prevalence of antibodies to Neospora caninum in mithun was 10% (95% CI=5-15) when detected by a commercially available competitive enzyme-linked immunosorbent assay test. Highest (prevalence rate=16, 95% CI=8-24) seroprevalence was found in mithuns above 3 years of age and lowest (prevalence rate=2, 95% CI=0-6) in mithuns of 2-12 months old. No statistically significant difference was observed between male (prevalence rate=7, 95% CI=0-14) and female (prevalence rate=12, 95% CI=6-18) seroprevalences. The seroprevalence was found to be higher (prevalence rate=20, 95% CI=9-31) in mithuns found in free-ranging condition in comparison to mithuns kept in semi-intensive system (prevalence rate=5, 95% CI=1-9). This is probably the first report on serological evidence of N. caninum infection in mithun. The possible role of sylvatic fauna in the epidemiology of N. caninum infection mithun is also discussed in brief.     

Seroprevalence of Toxoplasma gondii among Nunavik Inuit (Canada)

As a result of their intimate contact with the land and their nutritional habits, the Inuit of Nunavik are considered to be at risk from zoonotic infections. To better understand the risk factors for Toxoplasma gondii infection, a serosurvey was conducted in Nunavik, Québec, in September 2004. A representative sample of the Inuit adult population of Nunavik participated in this cross-sectional study (n = 917). Antibodies (IgG) against T. gondii were detected by immunoassay. Information on sociodemographic characteristics, traditional activities, domestic environment and nutrition was gathered by questionnaire and explored as variables explanatory of seropositive results. Associations found to be statistically significant in univariate analyses were assessed by multivariable logistic regression to control for confounding factors. Almost two thirds (59.8%) of the Inuit of Nunavik were found to be seropositive for T. gondii. In multivariate analyses, risk factors for seropositivity were: increasing age, gender (women > men), lower level of education, consumption of potentially contaminated water (determined by an index of risk from waterborne infections), frequent cleaning of water reservoirs, and consumption of seal meat and feathered game. There was some variation in seroprevalence between the Ungava Bay coast (52.3%) and the Hudson Bay coast (65.6%), the two main regions of Nunavik, but this variation was not significant in the multivariable logistic regression model. This cross-sectional study demonstrated high T. gondii seroprevalence in the Inuit population and revealed that age, gender, schooling and community of residence all influence serostatus in this population. Variables related to drinking water and food choices may also influence the risk of infection. These results raise important questions about T. gondii transmission in Nunavik including possible links between terrestrial and marine cycles.     

Seroprevalence of Toxoplasma gondii and Neospora caninum in captive maned wolves (Chrysocyon brachyurus) from southeastern and midwestern regions of Brazil

The main purpose of the present study was to investigate the occurrence of antibodies against T. gondii and N. caninum in captive maned wolves from Brazil, considering that little information is available at the literature about infections by these parasites in this wild animal. Serum samples were obtained from 59 maned wolves originated from six zoos and from one ecological reserve of the southeastern and midwestern regions of Brazil. To detect IgG antibodies against T. gondii, an ELISA protocol was used and the results were expressed as ELISA reactivity indexes (EI). Serology for N. caninum was carried out by indirect fluorescent antibody test (IFAT) and cut-off titers were established at 1:25 dilution. From the total of the analyzed samples, 44 (74.6%) were seropositive for T. gondii and only 5 (8.5%) for N. caninum. Seropositivity for T. gondii ranged from 0 to 100% in the seven different origin locals, with rates over 50% among the six zoos, whereas no positivity was found in the samples from ecological reserve. For N. caninum, seroprevalence varied from 0 to 50% in the different locals, with the highest rates also detected in zoos. Seroprevalence for T. gondii was strongly related with age, with rates significantly higher among adult wolves (91.7%) when compared to newborn or young animals. Seropositive samples for N. caninum were found predominantly in adult wolves. For both parasites, seroprevalence did not show a significant distinction in relation to gender. Although seroprevalence for T. gondii was significantly higher when compared to N. caninum in the Brazilian captive maned wolves tested, these findings reflect the great exposure of this species to T. gondii and, in lower extension, to N. caninum. Also, the present study demonstrated for the first time the presence of antibodies to N. caninum in wild life from South America.     

Seroprevalence of Toxoplasma gondii antibodies in clinically ill cats in the United States

OBJECTIVE: To determine regional seroprevalence estimates of Toxoplasma gondi-specific IgM and IgG in clinically ill cats throughout the United States. Sample Population-Sera from 12,628 clinically ill, client-owned cats. PROCEDURE: Toxoplasma gondii-specific IgM and IgG antibodies were detected by use of ELISAs. Sera from clinically ill cats previously submitted for T. gondii antibody testing were sequentially selected from our serum bank and the sample submission paperwork reviewed. The country was divided into 12 geographic regions. Overall prevalence as well as prevalence for each region, age group, season, sex (male vs female), and breed (domestic shorthair vs other) was calculated. Data were analyzed by logistic regression analysis. RESULTS: Overall, 31.6% of the cats were seropositive for T. gondii-specific IgM, IgG, or both. Percentage of cats seropositive for T. gondii antibodies ranged from 16.1% (southwestern United States) to 43.5% (northeastern United States). As age increased, odds of positive T. gondii antibody assay results (IgM alone, IgG alone, and any combination of IgM or IgG) increased. Males were more likely than females to be seropositive for T. gondii antibodies (IgG alone and any combination of IgM or IgG). Domestic shorthair cats were more likely than other breeds to be seropositive for T. gondii antibodies (IgM alone, IgG alone, and any combination of IgM or IgG). CONCLUSIONS AND CLINICAL RELEVANCE: Toxoplasma gondii-specific antibodies are common in serum samples of clinically ill cats from all regions of the United States. Seroprevalence increases as cats age and is higher in male and domestic shorthair cats, compared with females and other breeds.     

Seroprevalence of antibodies to Encephalitozoon cuniculi and Toxoplasma gondii in farmed domestic rabbits in Egypt

Rabbit sera from ten commercial farms representing three provinces in Northern Egypt (Behera, Alexandria and Khafr El-Sheikh) were submitted to serological screening for Encephalitozoon cuniculi using an enzyme-linked immunosorbent assay and for Toxoplasma gondii using an indirect hemagglutination test. Antibodies against E. cuniculi were detected in 36/240 (15%) sera examined while antibodies against T. gondii showed a seroprevalence of 22/194 (11.34%). Both infections were detected in all of the examined farms. These results are of epidemiological relevance and public health importance because of the recognized susceptibility of humans to E. cuniculi and T. gondii infections; therefore, routine screening examinations of farm rabbits are advised considering the zoonotic potential of these parasites.     

Genotyping of Toxoplasma gondii isolates from chickens from India

The present study was undertaken to isolate and genotype Toxoplasma gondii from free-range chickens (Gallus domesticus) from villages in Maharashtra and Tamil Nadu states of central and south India, respectively. Blood, heart, and brain from a total of 741 chickens were examined for T. gondii infection. Antibodies to T. gondii, as assayed with the modified agglutination test (MAT >or = 1:5) were found in 133 (17.9%) chickens. Hearts and brains of 186 chickens were bioassayed in mice. Additionally, hearts and/or brains of most of the seronegative (MAT < 1:5) chickens were fed to 20 T. gondii-free cats, while 32 seropositive chickens (MAT 1:5) were fed to 3 cats. T. gondii was not isolated from any of the chickens by mouse bioassay. Five of the cats that were fed seronegative chickens shed oocysts, while isolates were not obtained from any of the other cats fed seropositive chickens. These five isolates, along with the two that were previously isolated in India through cat bioassay, were genetically analyzed. Genotyping using the SAG 2 locus indicated that two isolates were type II and five were type III. Microsatellite analysis revealed allelic differences between and within the lineages. This is the first report of genetic characterization of any T. gondii isolate from India.     

Seroprevalence of Toxoplasma gondii infection in Norwegian dairy goats

Background

Toxoplasma gondii is a major problem for the sheep industry as it may cause reproduction problems. The importance of T. gondii in Norwegian goat herds is uncertain, but outbreaks of toxoplasmosis in dairy goat farms have been recorded. The aim of this study was to describe the prevalence of T. gondii infection in Norwegian dairy goats by using serology.

Findings

Goat serum originally collected as part of two nationwide surveillance and control programmes between 2002 and 2008 were examined for T. gondii antibodies by using direct agglutination test. In total, 55 of 73 herds (75%) had one or more serologically positive animals, while 377 of 2188 (17%) of the individual samples tested positive for T. gondii antibodies.

Conclusions

This is the first prevalence study of T. gondii infection in Norwegian goats. The results show that Norwegian goat herds are commonly exposed to T. gondii. Nevertheless, the majority of goat herds have a low prevalence of antibody positive animals, which make them vulnerable to infections with T. gondii during the gestation period.