Why new coronavirus variants emerge, and what that means for you
Image: Ritzau Scanpix/Henning Bagger via Reuters via PBS NewsHour
variants, efficacy, infection rates
The devastating spike in new daily COVID-19 cases in the United States has slowly begun to come down, and vaccinations are starting to protect millions of the country’s most vulnerable people.
But any respite from the pandemic’s worst chapter so far could be turned back — or made worse — by new coronavirus variants that experts say may present a variety of challenges to getting the virus under control.