Risk factors associated with Toxoplasma gondii seroprevalence in goats in the State of Paraíba, Brazil

Seroprevalence of Toxoplasma gondii infection in sheep and goats from different geographical regions of the world: Systematic review and meta-analysis

The Toxoplasma gondii is an obligate intracellular protozoan parasite which significantly impact small ruminant productivity, international animal trade and transboundary movement of animal across the globe. The seroprevalence of T. gondii infection (toxoplasmosis) in sheep and goats is widely studied in many parts of the world and there is a lack of comprehensive information on prevalence estimates considering the global and regional perspectives. The aim of the study was to use systematic review and meta-analysis methods to estimate the global and regional pooled seroprevalence of T. gondii infection in sheep and goats, as well as factors that influence prevalence estimations. Relevant articles reporting the seroprevalence of toxoplasmosis in sheep and/goats were searched in five electronic databases, including PubMed, Web of Science, Scopus, Embase and ProQuest. After the publications were checked to verify they fit the inclusion criteria, a total of 225 articles were included in the systematic review and meta-analysis, reflecting data from 70 countries/regions. The pooled prevalence was estimated using a random effect meta-analysis model. Overall, the seroprevalence of T. gondii infection was 33.86% (95% CI: 30.47-37.25%) in sheep and 31.78% (95% CI: 28.99-34.58%) in goats, with significant variation in prevalence estimates across geographical locations (p < .001). Substantial heterogeneity (I²  > 75%) was observed in most pooled seroprevalence estimates. The T. gondii infection in global sheep and goat population showed uptrend over the period. This information would be useful for epidemiologist, health authorities and farmers in order to plan future T. gondii survey and infection management strategies both locally and internationally.

A systematic literature review and meta-analysis of Toxoplasma gondii seroprevalence in goats

The aim of this study was evaluate to seroprevalence of Toxoplasma gondii in goats worldwide and the main risk factors associated from 2000 to 2020, through meta-analysis with 55,317 goats from 75 reports published in seven electronic databases of major global importance. A global seroprevalence detected was 27.49% (95% CI 24.15-30.95; I2 = 99%), with the lowest percentage in Asia (20.74%; 95% CI 16.45-25.39) and highest in Central America (62.15%; 95% CI 57.28-66.90) and Europe (31.53%; 95% CI 21.71-42.26). The seropositivity in Africa and South America were (29.41%; 95% CI 19.11-40.89) and (29.76%; 95% CI 25.84-33.83), respectively. The seroprevalence was associated with presence of cats (OR 2.22; 95% CI 1.30-3.82), goats older than one year (OR 1.77; 95% CI 1, 37-2.29), females (OR 1.43; 95% CI 1.23-1.65), rearing system (extensive vs. intensive) (OR 4.82; 95% CI 1.96-11, 84) and rearing system (semi-intensive vs. intensive) (OR 1.48; 95% CI 1.48-6.13). The heterogeneity was evidenced in most world regions and the risk factors may play roles in varying the seroprevalence.

Prevalence and isolation of Toxoplasma gondii in goats slaughtered for human consumption in the semi-arid of northeastern Brazil

The aim of this study was to determine the seroprevalence of anti-Toxoplasma gondii antibodies and factors associated with infection in goats, and to isolate protozoan strains in tissue samples from seropositive goats that were destined for human consumption in the state of Paraíba, northeastern Brazil. Serum samples from 229 slaughtered goats were tested using the indirect fluorescence antibody test (IFAT), with a cutoff point of 1:64. Epidemiological questionnaires were applied to the producers, to acquire information about the sanitary management used in their herds. Tissue samples from the animals were collected during slaughter, in order to perform bioassays in mice. The seroprevalence found was 21.39% (49/229), with antibody titers ranging from 1:64 to 1:32,768. The municipalities of origin, Patos (OR: 3.047; CI: 1.384-6.706) and Sousa (OR: 3.355; CI: 1.536-7.327), were considered to be factors associated with infection by T. gondii. Thirty-eight bioassays were performed in mice, using tissues from seropositive goats, with an isolation rate of 50% (19/38). There was no correlation between isolation rate and antibody titers. Only one mouse died, at 30 days post-infection, which demonstrated that the strains isolated had low virulence towards mice. It was concluded that there is high seroprevalence in goats in northeastern Brazil, as well as a high percentage of viable tissue cysts in slaughtered animals destined for human consumption. These results demonstrate that there is an imminent one health problem relating to toxoplasmosis, especially in the most populous municipalities in the study (Patos and Sousa), which were identified as factors associated with T. gondii infection in goats.

Ocular Disease in Mice Inoculated with Pork Heart Samples Infected with Toxoplasma gondii

PURPOSE

We analyzed the frequency, viability, and genetic characteristics of T. gondii in pork heart samples.Methods: Thirty-five fresh pork samples were purchased in a slaughterhouse in Erechim city. The DNA was extracted and qPCR was performed. T. gondii genotyping was performed using PCR-RFLP analysis. Positive samples were digested and inoculated in mice for viability analysis.Results: Our results showed that T. gondii DNA was detected in 25.7% of the pork heart samples and genotyping revealed one new atypical strain. The viability analyses demonstrated that 40% of mice presented clinical signs of T. gondii infection. qPCR was positive in the lung, liver, and brain of mice that presented clinical signs of T. gondii infection. Also, the histopathology analysis showed retinal disorganization, retinal detachment, inflammatory cell infiltration, and fibrosis in the eyes analyzed.Conclusion: Our findings have shown that pork eat from southern Brazil may contain live T. gondii that could be associated with toxoplasmosis.

Public health and economic importance of Toxoplasma gondii infections in goats: The last decade

Toxoplasma gondii infections are common in humans and animals worldwide. Toxoplasmosis in goats continues to be of public health and economic concern. The present review summarizes worldwide information on the prevalence of clinical and subclinical infections, epidemiology, diagnosis, treatment, and genetic diversity of T. gondii in goats in the past decade. There is debate and uncertainty regarding excretion of T. gondii in milk and the ingestion of raw milk as sources of T. gondii infection for humans. Toxoplasmosis can cause abortion and deaths even in adult goats. PCR-RFLP typing of T. gondii DNA derived from viable T. gondii isolates has revealed genetic diversity in goats in North and South America. The significance of T. gondii isolates in domestic goats usually associated with wildlife in USA is discussed. This review will be of interest to biologists, parasitologists, veterinarians, and public health workers.

Occurrence of anti-Toxoplasma gondii antibodies in meat and dairy goat herds in Rio Grande do Norte, Brazil

Toxoplasmosis is caused by Toxoplasma gondii, which is the main causative agent of abortion in small ruminants. Goats are among the animals that are most susceptible to this protozoon, and the disease that it causes leads to significant economic losses and has implications for public health, since presence of the parasite in products of goat origin is one of the main sources of human infection. Because of the significant economic impact, there is an urgent need to study the prevalence of T. gondii infection among goats in Sertão do Cabugi, which is the largest goat-producing region in Rio Grande do Norte. In the present study, the ELISA assay was used to test 244 serum samples from nine farms, located in four different municipalities in the Sertão do Cabugi region, which is an important goat-rearing region. The results showed that the prevalence of anti-T. gondii antibodies was 47.1% and that there was a significant association between positivity and the variables of age (≥ 34 months), location (Lajes, Angicos and Afonso Bezerra) and farm (all the farms). The avidity test was applied to all the 115 ELISA-positive samples to distinguish between acute and chronic infection. One hundred and three samples (89.6%) displayed high-avidity antibodies, thus indicating that most of the animals presented chronic infection, with a consequent great impact on the development of the goat production system and a risk to human health.