March 18, 2021 https://news.arizona.edu/story/novel-coronavirus-circulated-undetected-months-f… UArizona News and UC San Diego A new study dates emergence of the virus that causes COVID-19 to as early as October 2019. Simulations also suggest that in most cases, zoonotic viruses die out naturally before causing a pandemic. Related Improving Health Related Researchers Michael Worobey