"As these viruses continue to evolve, public health officials watch carefully to see whether new strains will be more easily ...

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 ...

Doctors across multiple countries are flagging a painful new COVID-19 symptom tied to a fast-spreading variant: a sore throat so severe that patients compare it to swallowing razor blades. The symptom ...

MARIN COUNTY, Calif. -- As the Delta variant spreads, we are learning more about breakthrough COVID-19 cases. Numbers from California's state health department help put into perspective what the ...

North Carolina's summertime COVID-19 spike is putting the state back in a troublesome spot: back above 1,000 daily cases; the Delta variant spreading fast; and still way too many unvaccinated people.

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 ...

Six years after the start of the COVID-19 pandemic, the virus still exists. A public health expert explains what Long COVID ...

As 56 million school children return to the classroom, the debate over masks in school rages -- along with the Delta variant. "The Delta variant is really effective at making copies of itself," says ...

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 coronavirus delta variant first discovered in India has now spread around the world, prompting further waves of infections in countries like the U.K. Now, there are increasing signs that mainland ...