The new Omicron variant of coronavirus, with its many mutations and seemingly quick spread in South Africa, is worrying scientists and government officials. But doctors want to remind Americans that ...

The subvariant — which is thought to have emerged in the U.K. over the summer — has two additional mutations affecting its spike protein, part of the virus's structure used to infiltrate cells.

LONDON — A newly-discovered mutation of the delta variant is being investigated in the U.K. amid worries that it could make the virus even more transmissible and undermine Covid-19 vaccines further.

Omicron spawn XBB.1.5, also known as "Kraken," now dominates the U.S. COVID variant scene, comprising an estimated 61% of cases, according to federal health data released Friday. But there's now a new ...

One thing we know for sure about SARS-CoV-2, the virus that causes COVID-19, is that it keeps changing. Since the start of the pandemic, we have seen several notable variants, including Alpha, Beta, ...

As the delta variant of coronavirus continues to spread across the world, a relative of the deadly strain is sparking concerns among health officials in South Korea, one of several countries to record ...

The coronavirus mutant that is now dominant in the United States is a member of the omicron family, but scientists say it spreads faster than its omicron predecessors, is adept at escaping immunity ...