Infection of African buffalo (Syncerus caffer) by oryx bacillus, a rare member of the antelope clade of the Mycobacterium tuberculosis complex.
Mycobacterium tuberculosis complex species cause tuberculosis disease in animals and humans. Although they share 99.9% similarity at the nucleotide level, several host-adapted ecotypes of the tubercule bacilli have been identified. In the wildlife setting, probably the most well-known member of this complex is Mycobacterium bovis, the causative agent of bovine tuberculosis. The recently described oryx bacillus is an extremely rare slow-growing member of the antelope clade of the M. tuberculosis complex and is closely related to the dassie bacillus, Mycobacterium africanum and Mycobacterium microti. The antelope clade is a group of strains apparently host adapted to antelopes, as most described infections were associated with deer and antelope, most specifically the Arabian oryx (Oryx leucoryx). In this study, oryx bacillus was isolated from a free-ranging adult female African buffalo (Syncerus caffer), in good physical condition, which tested strongly positive on three consecutive comparative intradermal tuberculin tests. Upon necropsy, a single pulmonary granuloma and an active retropharyngeal lymph node was found. Comprehensive molecular genetic assays were performed, which confirmed that the causative microorganism was not M. bovis but oryx bacillus. Oryx bacillus has never been reported in Southern Africa and has never been found to infect African buffalo. The identification of this microorganism in buffalo is an important observation in view of the large and ever-increasing epidemic of the closely related M. tuberculosis complex species M. bovis in some African buffalo populations in South Africa.
Department of Science and Technology/National Research Foundation Centre of Excellence for Biomedical Tuberculosis Research/Medical Research Council Centre for Molecular and Cellular Biology/Division of Molecular Biology and Human Genetics, Faculty of Health Sciences, Stellenbosch University, PO Box 19063, Tygerberg, 7505, South Africa. ngvp@sun.ac.za
Nicolaas C
NC
Gey van Pittius
Keith D
KD
Perrett
Anita L
AL
Michel
Dewald F
DF
Keet
Tiny
T
Hlokwe
Elizabeth M
EM
Streicher
Robin M
RM
Warren
Paul D
PD
van Helden
D000818:Animals; D015373:Bacterial Typing Techniques / Q000662:veterinary; D002020:Buffaloes / Q000382:microbiology*; D004269:DNA, Bacterial / Q000032:analysis; D005260:Female; D009169:Mycobacterium tuberculosis / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity; D010802:Phylogeny; D011110:Polymorphism, Genetic; D013019:South Africa / Q000453:epidemiology; D013045:Species Specificity; D014376:Tuberculosis / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*
D004269:DNA, Bacterial