In December 2019, a new illness was first detected in Wuhan, China. We now know this to be another outbreak of coronavirus in humans (the 7th). The virus has been named SARS-CoV-2 and the disease it causes is COVID-19.
As of March 6, 2020 over 100,685 cases and 3,411 deaths have been reported. The WHO currently estimates the case fatality rate at 3.4%, which is significantly less than the case fatality rate of SARS. The case counts are dramatically rising in part due to increased surveillance and testing.
While the outbreak seems to be centered in Wuhan, which is now under quarantine, the virus has spread throughout China and abroad, including Hong Kong, Singapore, Japan, and Thailand, as well as Europe, North America, South Asia, the Middle East, Africa, and Australia. Local transmission outside of China has been reported.
The origin of the virus is still unclear, however genomic analyis suggests SARS-CoV-2 is most closely related to viruses previously identified in bats. It is plausible that there were other intermediate animal transmissions before the introduction into humans. There is no evidence of snakes as an intermediary.
This work is made possible by the open sharing of genetic data by research groups from all over the world. We gratefully acknowledge their contributions. Special thanks to Kristian Andersen, David Blazes, Peter Bogner, Matt Cotten, Ana Crisan, Gytis Dudas, Vivien Dugan, Karl Erlandson, Nuno Faria, Jennifer Gardy, Becky Kondor, Dylan George, Ian Goodfellow, Betz Halloran, Christian Happi, Jeff Joy, Paul Kellam, Philippe Lemey, Nick Loman, Sebastian Maurer-Stroh, Oliver Pybus, Andrew Rambaut, Colin Russell, Pardis Sabeti, Katherine Siddle, Kristof Theys, Dave Wentworth, Shirlee Wohl and Nathan Yozwiak for comments, suggestions and data sharing.