Rob Stein - NPR

Rob Stein - NPR

A 3D reconstruction of the woolly mammoth genome might help revive the extinct species

A skin sample from a 52,000-year-old woolly mammoth offers new insights into what made the animals tick — and could help de-extinction efforts.
a dog

Rabies prompts new CDC rules for bringing dogs to the U.S.

Owners must confirm dogs either have a valid rabies vaccine or haven't been in a country where rabies is endemic in the last six months.

Delta variant of the coronavirus could dominate in U.S. within weeks

The variant, first identified in India, is the most contagious yet and, among those not yet vaccinated, may trigger serious illness in more people than other variants do, say scientists tracking the spread of infection.

U.S. vaccinations may be reaching a tipping point to stop the virus, experts say

While some researchers says it's still too soon to know for sure, a growing number of epidemiologists, infectious disease researchers and public health experts think the country might have reached — or be about to reach — that crucial inflection point.