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bioRxiv · 10.1101/2020.02.06.936807

Brucella species circulating in wildlife in Serengeti ecosystem, Tanzania

Sambu, R. M.·Mathew, C.·Nonga, H. E.·Lukambagire, A. S.·Yapi, R. B.·Fokou, G.·Keyyu, J.·Bonfoh, B.·Kazwala, R. R.
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Abstract

BackgroundBrucellosis is a bacterial zoonosis of public health and economic importance world-wide. It affects a number of domestic animals, wildlife and humans. This study was carried out to determine circulating Brucella species in wildlife in Serengeti ecosystem using molecular techniques. MethodologyA total of 189 samples including EDTA blood, serum and amniotic fluid from buffalos, lions, wildebeest, impala, zebra and hyena that were collected in relation to different cross-sectional studies conducted in the Serengeti ecosystem in Tanzania were used. Multiplex polymerase chain reaction AMOS-PCR and quantitative Real-Time PCR (qPCR) targeting the genus specific surface protein bcsp31 gene and the insertion sequence IS711 element downstream of the alkB gene for B. abortus and BMEI1162 gene for B. melitensis were employed on the samples. ResultsResults indicated that out of 189 samples examined, 12 (6.4%) and 22 (11.6%) contained Brucella DNA as detected by AMOS-PCR and qPCR, respectively. Most of the positive samples were from lions (52.6%) and buffaloes (19.6%). Other animals that were positive included wildebeest, impala, zebra and hyena. Out of 22 positive samples, 16 (66.7%) were identified as B. abortus and the rest were B. melitensis. ConclusionDetection of zoonotic Brucella species in wildlife suggests that livestock and humans at the interface areas where there is high interaction are at risk of acquiring the infection. Therefore, public education to interrupt risky transmission practices is needed. The findings also shed light on the transmission dynamics around interface areas and the role of wildlife in transmission and maintenance of Brucella infection in the region.

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Sambu, R. M., Mathew, C., Nonga, H. E., Lukambagire, A. S., Yapi, R. B., Fokou, G., Keyyu, J., Bonfoh, B., Kazwala, R. R.. 2020-02-06. Brucella species circulating in wildlife in Serengeti ecosystem, Tanzania. https://doi.org/10.1101/2020.02.06.936807

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