In the late 60's, the entire gaur (bison) population of Nagerhole Mahumalai wildlife sanctuary had been wiped out by an epidemic. Fortunately, no major epidemic has broken out after than but some
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/tigers-die-tb-officials-are-clueless
[2] http://admin.indiaenvironmentportal.org.in/category/newspaper/indian-express-new-delhi
[3] http://admin.indiaenvironmentportal.org.in/category/thesaurus/wildlife