NEW YORK (AP) — A new analysis of blood samples from 24,000 Americans taken early last year is the latest and largest study to suggest that the new coronavirus popped up in the U.S. in December 2019 — weeks before cases were first recognized by health officials.
The analysis is not definitive, and some experts remain skeptical, but federal health officials are increasingly accepting a timeline in which small numbers of COVID-19 infections may have occurred in the U.S. before the world ever became aware of a dangerous new virus erupting in China.
The pandemic coronavirus emerged in Wuhan, China in late 2019. Officially, the first U.S. infection to be identified was a traveler — a Washington state man who returned from Wuhan on Jan. 15 and sought help at a clinic on Jan. 19.
CDC officials initially said the spark that started the U.S. outbreak arrived during a three-week window from mid-January to early February. But research since then — including some done by the CDC — has suggested a small number of infections occurred earlier.