A ferocious surge of flu cases is linked in part to a variant that has not been dominant in the past few years — resulting in ...

A global study has found strong evidence that a new form of the coronavirus has spread from Europe to the US. The new mutation makes the virus more likely to infect people but does not seem to make ...

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 ...

Across the world, only a few dozen people appear to carry a genetic glitch that lets them brush off viruses that flatten ...

A variant strain of the coronavirus, one that was first discovered in the United Kingdom, is now the dominant strain of the virus circulating throughout the United States, CDC Director Rochelle ...

Bird flu has always worried pandemic planners, but a new twist is raising the stakes: scientists are now tracking variants that can keep multiplying even when a human body turns up the heat. A strain ...

At least 14 states and Washington, DC, are reporting high or very high flu activity. The dominant flu strain, a version of influenza A (H3N2) called subclade K, has multiple mutations that make it ...

After a sharp uptick in flu cases in mid-December 2025, flu activity across the U.S. and Canada remains high.