Coronavirus may have been circulating undetected in the US for 6 weeks

By Debora MacKenzie

Anthony Behar/Sipa USA

Covid-19 could well already be circulating within the US, in step with identical genetic sequences in viruses from two of us that contracted the disease quite a lot of weeks aside. One comes from a present case in Snohomish County, Washington, whereby the infected individual had no contact with one more case or outbreak residing. No matter this, the sequence of the virus in their sample closely fits that of the first infection detected within the US, on 21 January, in a man within the same county who had visited Wuhan.

Both sequences, that were posted to …