CAMBRIDGE, UNITED KINGDOM — Researchers from the University of Cambridge and Germany have used RNA analysis to identify three types of COVID-19 that evolved during the early stages of the pandemic. This study is published in the Proceedings of the National Academy of Sciences.<br /><br />Citing the team, the University of Cambridge writes in a news release that COVID-19 type A is the "original human virus genome" from the Chinese city of Wuhan.<br /><br />Mutated versions of type A were discovered in U.S. nationals who reportedly lived in Wuhan. Large numbers of type A virus were also seen in patients living in the U.S. and Australia.<br /><br />Strangely, the dominant variant in Wuhan was type B, which was prevalent across East Asia, but did not spread much beyond the region. This means either a complex founding event happened in Wuhan, or some factors had resisted type B outside East Asia."<br /><br />Type C is the main COVID-19 variant in Europe. The presence of type C was detected in early cases from France, Italy, Sweden and England, yet this variant was absent in samples from patients in Mainland China.