They are usually linked to the Huanan Seafood Wholesale Market, which also sold live animals. According to one theory, the virus came from one of these animals; in other words, it would have a zoonotic origin. An outbreak of pneumonia of unknown cause was observed on December 26 and treated by Dr. Zhang Jixian at Hubei Province Hospital, who notified Wuhan Jianghan CDC on December 27.
Haya yalihusishwa na Soko la Jumla la Samaki Huanan, ambayo pia iliuza wanyama walio hai, na nadharia moja ni kuwa virusi vilikuja kupitia mojawapo ya aina ya wanyama hawa; au, kwa namna nyingine, ina chanzo cha kutoka kwa wanyama hadi binadamu.Vikundi vya mchochota wa pafu ambazo chanzo chao haijulikani ilitambuliwa tarehe 26 Desemba na kutibiwa na daktari Zhang Jixian katika Hospitali ya Mkoa ya Hubei, ambaye alijulisha CDC iliyo Wuhan Jianghan tarehe 27 Desemba.