Several COVID-19 variants are acting uniquely enough to qualify as a distinct strain. And you might have heard about one on ...

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 ...

WASHINGTON - In a press briefing Friday, the head of the WHO said the delta variant is "quickly becoming the dominant strain in many countries," and thus, the world is in a "very dangerous period" of ...

The delta coronavirus variant surging across the United States appears to cause more severe illness and spread as easily as chickenpox, according to an internal document from the US Centers for ...

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 ...

SAN FRANCISCO (KGO) -- Bay Area doctors and health officials are concerned about the rapid spread of the COVID-19 Delta variant, warning significant outbreaks could trigger a setback for the state.

The more contagious Delta variant of Covid-19 now makes up 83% of sequenced samples in the United States, US Centers for Disease Control and Prevention Director Dr. Rochelle Walensky said Tuesday.

NEW YORK, N.Y. — Pfizer announced Wednesday that data shows a third dose of its COVID-19 vaccine can “strongly” boost protection against the highly transmissible delta variant. The pharmaceutical and ...

It is a stark reality. But in some parts of the country, the pandemic in 2021 is shaping up to be worse than it was in 2020. Covid case numbers are climbing rapidly, though they remain well below peak ...

As the delta COVID-19 variant continues to jeopardize progress against rising cases and hospitalizations around the world, the United States is shifting strategy when it comes to persuading ...

NEW YORK (WABC) -- New York City's latest COVID positivity rate is still low at 1.17 percent. Marriage bureaus in the city are opening on Monday for in-person weddings. However, there was a warning on ...