A new study of tuberculosis (TB) prevalence in captive elephants (presumably Elephas maximus) in India, reported in the Times of India, shows that approximately 15% of southern India's captive elephants test positive for TB. This is a big problem for the health and well-being elephants. The study makes me wonder (1) what TB prevalence in free-ranging elephants is, and (2) how frequently TB is transmitted from elephant to humans, and (3) what the infectious organism is (M. tuberculosis vs. M. bovis), (4) where do the infections of captive elephants come from: cattle, humans, other elephants?
The PROMED-mail moderator wrote the following on the topic of TB epidemiology in elephants. Elephants are known to be susceptible to infection by both Mycobacterium tuberculosis and M. bovis. The above article does not specify the bacteria identified in the Indian elephants. A short review on tuberculosis in elephants, by Susan Mikota, was published by ProMED-mail in July 2007 (see ProMED archive 20070702.2111). It included, among other things, the following: "While most cases in the U.S. have been due to M. tuberculosis, we may find more cases of M. bovis in Asia, where elephants often share grazing land with domestic livestock." The review, to which subscribers are referred, also covered data on the sampling and laboratory techniques applicable in elephants.