Corona Virus has many mutations and subtypes
https://academic.oup.com/nsr/advance-article/doi/10.1093/nsr/nwaa036/5775463
Researchers in China have found that two different types of the new coronavirus could be causing infections worldwide.
https://www.cnbc.com/2020/03/04/coronavirus-chinese-scientists-identify-two-types-covid-19.html