Until recently, TB had never been reported in a wild elephant. Then in 2013, TB was diagnosed in a wild African elephant that had been under human care at an orphanage. In 2015 TB was found in a wild elephant in Sri Lanka. Now in 2017 four cases of TB in wild elephants in India were reported in the on-line journal Emerging Infectious Diseases. Dr. Mikota discusses the threat of TB to wild elephants in this invite CDC podcast: https://www2c.cdc.gov/podcasts/player.asp?f=8645613
You can also read the 2017 reports in the March issue of Emerging Infectious Diseases:
Zachariah A, Pandiyan J, Madhavilatha G, Mundayoor S, Chandramohan B, Sajesh P, et al. Mycobacterium tuberculosis in Wild Asian Elephants, Southern India. Emerg Infect Dis. 2017;23(3):504-506. https://wwwnc.cdc.gov/eid/article/23/3/16-1741_article
Chandranaik B, Shivashankar B, Umashankar K, Nandini P, Giridhar P, Byregowda S, et al. Mycobacterium tuberculosis Infection in Free-Roaming Wild Asian Elephant. Emerg Infect Dis. 2017;23(3):555-557. https://wwwnc.cdc.gov/eid/article/23/3/16-1439_article