New vaccines are often evaluated in trials in which some participants receive a placebo. But not all studies can be designed this way.

With new testing requirements, it’s not even clear how new Covid or flu shots can be made available this fall.

Something was very wrong with Kyle and Nicole Muldoon’s baby. The doctors speculated. Maybe it was meningitis? Maybe sepsis? They got an answer when KJ was only a week old. He had a rare genetic disorder, CPS1 deficiency, that affects just one in 1.3 …

Students at Wyoming East High School in West Virginia’s coal country had different reasons for joining Raze, a state program meant to raise awareness about the health risks of tobacco and e-cigarettes. Cayden Oliver, 17, grew up around generations of …

The progress comes as the Trump administration is proposing to cut funding for many programs believed to have contributed to the improvement.

Kseniia Petrova, a Harvard researcher, was detained Feb. 16 at Logan Airport after failing to declare scientific samples she carried into the U.S.