The explosion of COVID-19 around the world had a longer fuse than early indications suggested. The World Health Organization team is briefed outside the market on their field visit in Wuhan on January 31, 2021. Now a new study in the journal Science suggests the first human infection occurred weeks to months before the market outbreak. The SARS-CoV-2 virus mutates on average once every two weeks, which allows the researchers to create a family tree of the viral genomes to trace back to the original ancestor. "In some ways, the stars aligned in just the wrong way in this pandemic," Worobey said.

Source: CBC News March 26, 2021 20:48 UTC