A study on clinical diagnosis of tuberculosis in free ranging and captive wild animals of India.

Background: Tuberculosis (TB) is a disease of paramount importance at the wildlife-livestock-human interface.

Aims: To study the occurrence and (M) species involved in the TB of free-ranging and captive wild animals in various Indian states.

Methods: A total of 396 clinical samples from 207 different wild animal species from various Indian national parks, zoological gardens, etc., were analyzed by lateral flow assay (LFA), Ziehl-Neelsen (ZN) staining, and PCR. Clinical samples include blood (n=156), faecal swabs (n=103), serum (n=73), and nasal swabs or trunk wash fluids (n=64).

Results: Clinical signs of TB were absent in 202 animals, although 21 wild animals were seropositive for pathogenic antigens by LFA. Clinical signs like progressive weight loss, and respiratory distress were exhibited by 4 sloth bears () and an elephant (), which were also found positive for LFA, PCR, and ZN staining. ZN staining showed positivity for acid-fast bacilli (AFB) in 9 (8.74%) faecal and 9 (14.06%) nasal swabs or trunk wash fluids of sloth bears (7 samples) and elephants (2 samples). was detected in 7 sloth bears and 2 elephants, whereas was found in a spotted deer () by species-specific PCR.

Conclusion: The circulation of TB organisms in wild animals warrants a strict surveillance programme to identify the carrier status of these animals so that effective TB control strategies can be formulated.