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

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 ...

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 ...