Neglected Tropical Diseases Congress: The Future Challenges

Biography

Biography: Robert Barigye

Abstract

To date, no studies known to the authors have specifically evaluated the seroprevalence of Brucella spp, C. burnetti, C. abortus and T. gondii in livestock in the UAE. In addition, there no data on the potential role these agents may be playing in reproductive failure in domesticated small ruminants in the country. Without such data, the anecdotal statements attributing abortions and other forms of reproductive failure in sheep and goats to brucellosis have no scientific merit and need to be empirically substantiated in the UAE. Moreover, the potential zoonotic risk posed by the livestock-associated pathogens needs to be elucidated in the UAE. A serological survey was carried out to determine the seroprevalence of Brucella spp, C. burnetii, C. abortus, and T. gondii in sheep and goat herds in the UAE. A total of 915 blood samples [n= 222, [sheep]; n= 215, [goats]) were collected from livestock farms in the Emirates of Abu Dhabi, Dubai, Sharjah and Ras Al-Khaimah (RAK). An additional 478 samples (n= 244, [sheep]; n= 234, (goats]) were collected from the Al Ain livestock central market and tested by indirect ELISA for pathogen-specific antibodies. Brucella antibodies were further corroborated by the Rose-Bengal agglutination test. Seropositivity for the four pathogens was variably documented in sheep and goats from the study area. Respectively, the overall livestock farm prevalence for Brucella spp, C. burnetii, C. abortus, and T. gondii were 2.7%, 27.9%, 8.1%, and 16.7% for sheep, and 0.0%, 31.6%, 9.3%, and 5.1% for goats. Additionally, the seroprevalence of Brucella spp, C. burnetii, C. abortus, and T. gondii in samples from the livestock market were 7.4%, 21.7%, 16.4%, and 7.0% for sheep, and 0.9%, 32.5%, 19.2%, and 11.1% for goats respectively. Overall, sheep had 12.59 more chances than goats of testing seropositive for Brucella spp (OR, 12.59 [95% CI 2.96 – 53.6]) but less likely to be positive for C. burnetii-antibodies (OR, 0.73 [95% CI 0.54 – 0.97]). Notably, the differences in the seroprevalence rates of C. abortus and T. gondii in sheep and goats were not statistically significant (p >0.050). The present data indicate that all the four study pathogens are present in sheep and goat populations in the UAE and that coxiellosis is the most seroprevalent followed by chlamydophilosis, toxoplasmosis, and brucellosis. While sheep from the livestock market were more likely than those from farms to be Brucella-seropositive, the overall exposure risk of C. burnetii appears to be greater for goats than sheep. As more animals from the livestock market were more likely to be seropositive to C. abortus, it is possible that under the UAE animal production conditions, at least, coxiellosis and chlamydophilosis are more likely to increase the culling rate of domesticated small ruminants than toxoplasmosis and brucellosis. While anecdotal reports have previously suggested that brucellosis may be a significant animal health risk in the UAE, the present data imply that C. burnetii, C. abortus and T. gondii may be more significant pathogens of sheep and goats in the country. However, the extent to which these pathogens may nationally be contributing to reproductive failure in sheep and goat herds is not known and needs to be investigated. Potentially, these agents may also carry a zoonotic risk to risk groups like farm workers, and slaughter house personnel. An ongoing study is evaluating the seroprevalence of bovine coxiellosis in the Emirate of Abu Dhabi and the data will further elucidate on the broader epidemiological dynamics of the disease in the national herd.