Tuberculosis in Tanzanian wildlife.

Bovine tuberculosis, caused by Mycobacterium bovis, is a pathogen of growing concern in free-ranging wildlife in Africa, but little is known about the disease in Tanzanian wildlife. Here, we report the infection status of Mycobacterium bovis in a range of wildlife species sampled from protected areas in northern Tanzania. M. bovis was isolated from 11.1% (2/18) migratory wildebeest (Connochaetes taurinus) and 11.1% (1/9) topi (Damaliscus lunatus) sampled systematically in 2000 during a meat cropping program in the Serengeti ecosystem, and from one wildebeest and one lesser kudu (Tragelaphus imberbis) killed by sport hunters adjacent to Tarangire National Park. A tuberculosis antibody enzyme immunoassay (EIA) was used to screen serum samples collected from 184 Serengeti lions (Panthera leo) and 19 lions from Ngorongoro Crater sampled between 1985 and 2000. Samples from 212 ungulates collected throughout the protected area network between 1998 and 2001 also were tested by EIA. Serological assays detected antibodies to M. bovis in 4% of Serengeti lions; one positive lion was sampled in 1984. Antibodies were detected in one of 17 (6%) buffalo (Syncerus caffer) in Tarangire and one of 41 (2%) wildebeest in the Serengeti. This study confirms for the first time the presence of bovine tuberculosis in wildlife of northern Tanzania, but further investigation is required to assess the impact on wildlife populations and the role of different wildlife species in maintenance and transmission.

Prevalence of bovine tuberculosis in cattle in different farming systems in the eastern zone of Tanzania.

The prevalence of bovine tuberculosis (BTB) infection in cattle was investigated in pastoral and intensive production systems in the eastern zone of Tanzania. The prevalence of BTB infection as determined by single comparative intradermal tuberculin test (SCITT) was 1.3%, whereas the non-specific infection prevalence was 6%. In the pastoral sector, the prevalences were 1 and 7%; under intensive systems, they were 2 and 6% for BTB and non-specific infections, respectively. The prevalences were significantly higher in the intensive than pastoral production systems. However, the prevalence of BTB infection was higher in the small-scale (3%) than in other production systems (0.6-1.1%). Non-specific infections were lowest in the small-scale dairy sector (4%) than in other dairy-production systems (6-11%). Out of 143 herds tested, 10 and 28% of herds in the intensive systems (small, medium and large farms) and 17 and 88% of the herds in the extensive system (pastoral farms) had both BTB and non-specific infections, respectively.