The delta variant is fueling the COVID-19 surge in the United States, but experts warn that a more dangerous variant could emerge if more Americans don't get vaccinated. Delta is the most recent of ...

The alpha variant has been the most prevalent lineage of the novel coronavirus in the United States since April, but the U.S. Centers for Disease Control and Prevention expects that is no longer the ...

Differing strains of the coronavirus continue to appear around the world and a new COVID-19 variant, the so-called "Delta" variant, has health experts concerned. The variant, otherwise known as B.1617 ...

With the Delta variant in play, federal health officials are analyzing the latest numbers to look at the frequency and seriousness of COVID-19 breakthrough infections. Will we need booster shots? And ...

We were unable to process your request. Please try again later. If you continue to have this issue please contact customerservice@slackinc.com. In a mostly vaccinated cohort, COVID-19 infections amid ...

LAS VEGAS, NEVADA -- A California couple says they were fully vaccinated, but still contracted COVID-19 while on vacation as experts say breakthrough cases are possible, especially with the delta ...

The Centers for Disease Control and Prevention listed the COVID-19 delta variant as one of its "variants of concern" (VOCs) on June 15. According to the CDC, VOCs can be more contagious, more ...

Last week, the number of COVID-19 cases in children in the US reached levels not seen since the winter surge. And with the return to school, the Delta variant on the rise and winter approaching, ...

Vaccine effectiveness against COVID-19 infection dropped from 91% to 66% once the delta variant accounted for the majority of circulating virus, according to a study published Tuesday by the U.S.