An author of a study that found masking to be ineffective says, "The underlying problem is...people are drunk with certainty. They're told if something works, end of story. That's not science. What science it's likely or unlikely to work or we can't find evidence of it."

Two pioneering scientists who created the technology behind life-saving Covid-19 vaccines have won the Nobel Prize in medicine or physiology.

Dr. Sanjay Gupta discusses how attention spans have changed and the way our brains have been affected by it. Listen to the new season of "Chasing Life" wherever you get your podcasts.

Christiane Amanpour speaks with historian Simon Schama about his new book "Foreign Bodies," a history of pandemics, vaccines and the health of nations.

An Arkansas toddler died of a rare brain-eating amoeba infection, which was likely contracted at a splash pad at a country club, according to health officials and the county coroner.