I wish to offer the following observations on the epidemiology of 2019-nCoV in Hubei Province, China, over the past few weeks. I hope that the thoughts below will be helpful to others trying to organize and interpret the flood of information that has emerged about this new pathogen.
Information from a variety of sources suggests that this novel virus is a recombinant betacoronavirus of animal origin that emerged in November or December 2019, likely at the Wuhan Seafood Market. Epidemiological analysis was initiated after recognition of a market-linked pneumonia cluster in late December. Notwithstanding the name of the “Wuhan Seafood Market”, the market sells large numbers of live animals, including wild animals, which are kept in close proximity to one another, perhaps facilitating viral recombination. Similar disrupted ecology contributed to the emergence of SARS.