In response , spokesperson Chinese Ministry Foreign Affairs posted Twitter account article allegedly demonstrating SARS-CoV-2 already present 2019 United States brought China American soldiers.The spread false information hamper response real epidemics , therefore crucial establish verifiable facts SARS-CoV-2 virus.What know origins Covid-19 ? The results genomic analysis SARS-CoV-2 clear : sequence 96 % identical RaTG13 coronavirus isolated bat collected Chinese province Yunan.The sequence receptor binding domain ( RBD ) present surface SARS-CoV-2 allows infect human cells , however , diverges strongly equivalent sequence observed RaTG13.On hand , RBD sequence SARS-CoV-2 close ( 99 % ) coronavirus isolated pangolin.This suggests SARS-CoV-2 result recombination two viruses .