A case in which more than 200 kindergarten students in northwestern China were found to have abnormal blood lead levels is ...

Webcams have opened windows to nature that few people could have imagined just a couple of decades ago. Pick a spot, and ...

A contagious new COVID-19 variant called NB.1.8.1, aka "Nimbus," is now dominant in the United States, CDC data show. What to know about symptoms and vaccines.