Frequency of Detection of Immunoglobulins ofToxoplasma gondii, Leptospiraspp., andBrucella abortusin Livestock/Farm and Abattoir Workers in Trinidad

Prevalence of Toxoplasma gondii, Leptospira spp., and Coxiella burnetii-associated antibodies in dairy cattle with reproductive disorders

Background and Aim

In cattle dairy farms, abortions and other reproductive problems due to major infectious diseases are overlooked, and identifying their causative agents is very challenging without a confirmatory diagnosis. Further, a prevalence study in animals will provide important hints of pathogen reservoirs and provide necessary direction to disease burden with appropriate control and biosecurity measures at the farm level. This study aimed to estimate the prevalence of Toxoplasma gondii antibodies in dairy cattle associated with reproductive problems along with coexisting antibodies against abortifacient zoonotic (Coxiella burnetii and Leptospira spp.) pathogens.

Materials and Methods

Cattle sera (n = 246) from dairy farms (n = 35) situated in different locations in India were screened for anti-T. gondii and C. burnetii antibodies with enzyme-linked immunoassay and Leptospira spp. antibodies with microscopic agglutination test.

Results

The overall prevalence of 11.4% (95% confidence intervals [CIs]: 7.99%-15.96%) antibodies in cattle associated with reproductive problems (p < 0.021) with farm-level seropositivity of 43% was observed. Further, on analysis of screened sera, 49.8% (95% CI: 42.6%-55%) and 77.6% (95% CI: 72%-82.4%) of samples were found to be positive for C. burnetii and Leptospira spp. antibodies, respectively. Moreover, the seropositivity of 91.9% (226/246) for at least one of the screened zoonotic pathogens was observed, indicating antibodies against either of these organisms in association with reproductive disorders (p < 0.005). The percentage of cattle found to have T. gondii antibodies was only 1.8%, whereas 11.5% and 41.6% of cattle were found to have C. burnetii and Leptospira spp. antibodies, respectively. Nevertheless, the predominantly mixed infections observed were of Leptospira and C. burnetii (34.5%), followed by all three infections (4.9%); toxoplasmosis and leptospirosis (3.5%); and toxoplasmosis and Q fever (2.2%).

Conclusion

The serological detection of antibodies against these pathogens in cattle may have significant implications for the livestock industry and public health, suggesting the need for continuous surveillance and monitoring of these infections to prevent their spread.

Seroprevalence and Risk Factors of Toxoplasma gondii Infection Among High-Risk Populations in Jiangsu Province, Eastern China

Toxoplasma gondii, an opportunistic protozoan, infects one-third of people worldwide and could lead to serious outcomes in immunodeficient or immunocompromised populations. The present study aimed to investigate the prevalence and risk factors for T. gondii infection among high-risk populations in Jiangsu Province, eastern China. We conducted a cross-sectional survey among 4 categories of populations in 13 prefectures including HIV/AIDS patients, livestock breeding/processing (B/P) staff, pregnant women, and cancer patients. We detected specific immunoglobulin G and M (IgG and IgM) levels for each participant using enzyme-linked immunosorbent assay (ELISA) and asked to complete a questionnaire for each participant that covered sociodemographic information as well as the basic knowledge of attitudes toward and the practices for the prevention of toxoplasmosis. A total of 5231 participants distributed across 13 prefecture-level cities was surveyed, including 2455 males and 2776 females. Total seropositivity rate in each population category was as follows: 9.08% (HIV/AIDS patients), 11.65% (livestock B/P staff), 5.50% (pregnant women), and 12.89% (cancer patients). We detected IgM positivity in HIV/AIDS patients (0.47%, 6/1289), livestock B/P staff (0.08%, 1/1330), and cancer patients (0.46%, 6/1303) but not in pregnant women. Further, we detected IgM+IgG positivity only in cancer patients (0.31%, 4/1303). The seropositivity rate for pregnant women was significantly lower, while cancer patients were significantly higher. Higher educational levels were associated with lower seropositivity rates for T. gondii infection. High seropositivity rates were associated with long period of HIV infection among HIV/AIDS patients, frequent contact with livestock among livestock breeding/processing staff and male older patients among cancer patients, respectively. Analysis of practices across all participants showed that frequent contact with pets in everyday life or using the same cutting board for both raw and cooked foods leads to higher seropositivity rates. Therefore, we obtained the seroprevalence and risk factors of toxoplasmosis among high-risk populations in Jiangsu Province which could provide evidence for the implementation of control measures in the near future.

Serosurvey for Infectious Agents Associated with Subfertility and Abortion in Dairy Cattle in Trinidad and Tobago, West Indies

Despite frequent reports of subfertility and abortion in dairy cattle in Trinidad and Tobago (T&amp;T), little is known about the potential infectious and non-infectious causes. This study set out to investigate possible infectious causes of reproductive problems by measuring the seroprevalence of four of the most significant reproductive pathogens in dairy cattle worldwide: Brucella abortus (B. abortus); Neospora caninum (N. caninum), Bovine Viral Diarrhoea virus (BVDV), and Infectious Bovine Rhinotracheitis virus (IBRV). These four reproductive pathogens have been suspected to be present in dairy cattle in T&amp;T for some time but, previously, studies have not been carried out to confirm their presence. Bulk milk samples were collected from 92 dairy farms across Trinidad, representing a total of 1177 dairy cattle. Four dairy farms were selected for individual milk sampling to assess in-farm seroprevalence levels. Milk samples were tested for antibodies to the four pathogens by commercial ELISA kits. The overall farm seroprevalence was 62% for N. caninium and 23% for IBRV, and no antibodies were detected in any of the bulk milk samples for B. abortus or BVDV. Mixed infections for IBRV and N. caninum were common. Seroprevalence levels were between 8% and 65% for N. caninum and between 3% and 53% IBRV on the four individual farms. These results reveal the presence of IBRV and N. caninum for the first time on the island of Trinidad and importantly reveal no evidence for the circulation of BVDV or B. abortus in dairy cattle in Trinidad.