President Joe Biden said Thursday that the U.S. will have enough supply of the COVID-19 vaccine by the end of the summer to inoculate 300 million Americans.
The coronavirus most likely first appeared in humans after jumping from an animal, a team of international and Chinese scientists looking for the origins of COVID-19 said Tuesday, saying an alternate theory that the virus leaked from a Chinese lab was unlikely.
Evidence is mounting that having COVID-19 may not protect against getting infected again with some of the new variants. People also can get second infections with earlier versions of the coronavirus if they mounted a weak defense the first time, new research suggests.
The drive to vaccinate Americans against the coronavirus is gaining speed and newly recorded cases have fallen to their lowest level in three months, but authorities worry that raucous Super Bowl celebrations could fuel new outbreaks.