While overhunting and climate change have been the major hypotheses to explain the late-Pleistocene New World megafaunal extinctions, the role of introduced disease has only received brief attention. Here, we review pre-Columbian diseases endemic to aboriginal Americans and evaluate their potential to cause large-scale mortality in Pleistocene mammals. Of the probable communicable diseases present in pre-Columbian times, we regard anthrax and tuberculosis as viable candidates. These two diseases demonstrate characteristics that could have made them deadly to immunologically naïve populations. Introduced disease, as a primary cause or interacting with overhunting and climate change, could have contributed to the decline and extirpation of Pleistocene megafauna.
Nickell, Zachary D. and Moran, Matthew D.. "Disease Introduction by Aboriginal Humans in North America and the Pleistocene Extinction." Journal of Ecological Anthropology 19, no. 1 (2017): 29-41.
Available at: http://scholarcommons.usf.edu/jea/vol19/iss1/2