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Bovine tuberculosis (bovine TB) caused by Mycobacterium bovis has become endemic in some wildlife populations in South Africa. The disease has been reported in 21 wildlife species in the country. In this study, we report M. bovis infection in two female giraffes (Giraffa camelopardalis) from two different nature reserves within the Greater Kruger National Park Complex (GKNPC). Mycobacterium bovis was isolated from tissue lesions consistent with macroscopic appearance of tuberculosis (TB) and confirmed by polymerase chain reactions (PCRs), targeting the RD4 region of difference on the genome of the isolates. Spoligotyping and variable number of tandem repeat (VNTR) typing revealed infection of one giraffe with a strain (SB0294) previously not detected in South Africa, while a resident M. bovis strain (SB0121) was detected from the other giraffe. Our work is first to report M. bovis infection in free‐ranging giraffes in South Africa. We have further demonstrated the existence of at least three genetically unrelated strains currently infecting wildlife species within the GKNPC. This finding suggests that the epidemiological situation of M. bovis within the GKNPC is not only driven by internal sources from its established endemic presence, but can be additionally fuelled by strains introduced from external sources. It further emphasizes that regular wildlife disease surveillance is an essential prerequisite for the timely identification of new pathogens or strains in ecospheres of high conservation value. [ABSTRACT FROM AUTHOR]

Mycobacterium bovis (M.bovis) is the main causative agent for bovine tuberculosis (BTB) and can also be the cause of zoonotic tuberculosis in humans. In view of its zoonotic nature, slaughterhouse surveillance, potentially resulting in total or partial condemnation of the carcasses and organs, is conducted routinely.Spoligotyping, VNTR profiling, and whole genome sequencing (WGS)ofM. bovis isolated from tissues with tuberculosis-like lesions collected from 14 cattle at Eritrea’s largest slaughterhouse in the capital Asmara, were conducted.The 14 M. bovisisolates were classified into three different spoligotype patterns (SB0120, SB0134 and SB0948) and six VNTR profiles. WGSresults matched those of the conventional genotyping methodsand further discriminatedthe six VNTR profiles into 14 strains.Furthermore, phylogenetic analysis of the M. bovisisolates suggests two independent introductions of BTB into Eritrea possibly evolving from a common ancestral strain in Europe.This molecular study revealed the most important strains of M. bovis in Eritrea and their (dis)similarities with the strains generally present in East Africa and Europe, as well as potential routes of introduction of M. bovis. Though the sample size is small, the current study provides important information as well as platform for future in-depth molecular studies on isolates from both the dairy and the traditional livestock sectors in Eritrea and the region. This study provides information onthe origin of some of the M. bovis strains in Eritrea, its genetic diversity, evolution and patterns of spread between dairy herds. Such information is essential in the development and implementation of future BTB control strategy for Eritrea. [ABSTRACT FROM AUTHOR]

Background Bovine tuberculosis (bTB) is a chronic debilitating disease and is a cause of morbidity and mortality in livestock, wildlife and humans. This study estimated the prevalence and risk factors associated with bovine tuberculosis transmission in indigenous cattle at the humananimal interface in the Serengeti ecosystem of Tanzania. Results A total of 1,103 indigenous cattle from 32 herds were investigated for the presence of bTB using the Single Intradermal Comparative Tuberculin Test. Epidemiological data on herd structure, management and grazing system were also collected. The apparent individual animal prevalence of tuberculin reactors was 2.4% (95% confidence interval (CI), 1.7 - 3.5%), whereas the true prevalence was 0.6% CI, 0.6 - 0.7% as indicated by a reaction to avian tuberculin purified protein derivatives (PPD) which is more than 4 mm greater than the reaction to avian tuberculin PPD. The results showed that 10.6% (117/1,103) showed non-specific reactions (atypical mycobacterium). The herd prevalence of 50% (16/32) was found. Tuberculin skin test results were found to be significantly associated with age, location, size of the household and animal tested. Of 108 respondents, 70 (64.8%) individuals had not heard about bovine tuberculosis at all. Thirty five percent (38/108) of respondents at least were aware of bTB. About 60% (23/38) of respondents who were aware of bTB had some knowledge on how bTB is spread. Eighty one percent (87/108) of respondents were not aware of the presence of bTB in wildlife. There is regular contact between cattle and wild animals due to sharing of grazing land and water sources, with 99% (107/108) of households grazing cattle in communal pastures. Conclusion The study has demonstrated a high reported interaction of livestock with wildlife and poor knowledge of most cattle owners concerning bTB and its transmission pathways among people, livestock and wildlife. Although the overall proportion of animals with bTB is relatively low, herd prevalence is 50% and prevalence within herds varied considerably. Thus there is a possibility of cross transmission of bTB at wildlife-livestock interface areas that necessitates use of genetic strain typing methods to characterize them accurately. [ABSTRACT FROM AUTHOR]

Abstract: Vaccination has been discussed as a practical option to control bovine tuberculosis in countries where a wildlife reservoir of the disease is present. African buffaloes (Syncerus caffer) are the main wildlife reservoir of Mycobacterium bovis in certain South African game parks and vaccination is not only the most promising but the only ethically acceptable control measure currently available. The use of Bacillus Calmette-Guérin vaccine (Pasteur strain) to vaccinate fourteen African buffalo yearlings and their reactions to subsequent intratonsilar challenge with a field strain of M. bovis are described. The BCG vaccine was administered twice intramuscularly, six weeks apart. All vaccinates and thirteen control buffaloes were euthanized and necropsies performed 9 months after the challenge. Standard sets of lymph nodes from the head, the thoracic cavity and abdomen were cultured and examined histopathologically. No significant reduction in number of lesions or severity of disease was noted, concluding that the BCG vaccine did not induce sufficient protection able to limit the shedding of organisms. The age of the buffaloes, route of vaccination and prior exposure to environmental mycobacteria are among the possible reasons for vaccination failure. [ABSTRACT FROM AUTHOR]