> Previous examples of zoonotic sources have always turned up evidence in animal populations within a short time Which specific examples do you have in mind? I

> Previous examples of zoonotic sources have always turned up evidence in animal populations within a short time Which specific examples do you have in mind? In the case of the 2002 SARS outbreak, the most likely source wasn't identified until 2017: https://www.nature.com/articles/d41586-017-07766-9 https://www.nature.com/articles/d41586-017-07766-9