Abstract
Brucellosis negatively affects agricultural economies as well as animal and human health throughout Africa. Historically, the presence of Brucella in Cameroon has not been confirmed, and the disease situation not fully understood, as previous studies were based solely on serological tests. In this study, we attempt to better understand the disease extent in the major animal species of agricultural and public health concern including cattle, sheep, goats, and pigs within the most important regions of Cameroon in terms of trade, movement, and animal numbers (Far North, North, and West). Currently, blood, milk, urine, vaginal swab, hygroma fluid, placenta, and lymph node samples are being collected from each of the livestock species at slaughterhouses across each region. Serum and milk are subject to the Rose Bengal Test (RBT) for serology. All samples are subject to culture, as well as real-time PCR (RT-PCR). Countrywide, approximately 88% of sample collection, 82% RBT, 75% culture, and 9% RT-PCR has been completed. So far, RBT suggests a countrywide seropositivity of 6.79% for cattle, sheep (1.10%), goats (2.24%), and pigs (2.81%). Culture has resulted in 0.65% positivity for cattle and 0% in the other species. Although RT-PCR has only been conducted on 393 total animals, 10 cattle (5 North, 3 West, and 2 Far North) and 1 goat (West) have tested positive for Brucella abortus. To this point in our study, it appears that B. abortus is endemic across the country. Interestingly, despite the initial assumption that B. melitensis and B. suis are present, we have not yet identified the presence of these species. Furthermore, generalization that B. melitensis is a significant problem throughout Africa should not be assumed. Therefore, this study reveals that control strategies in Cameroon should likely be directed at cattle farming and the associated supply chain countrywide. Forthcoming, we will complete sampling and diagnostic assays, sequence DNA using whole genome sequencing, and conduct a region-specific epidemiologic risk investigation. Our overall findings within this project will serve to enhance the capabilities of the Cameroonian government, as well as human and animal health services to prevent, detect, and respond to the apparent brucellosis biothreat.
