From June through August, people in their 20s accounted for more than 20% of all COVID infections in the United States, CDC researchers found....

It was less than a month ago that the United States reached 6 million cases. It took over three months for the country to record its first million cases....

Patients who were vitamin D-sufficient -- a blood level of at least 30 nanograms per milliliter -- had a significantly lower risk for serious complications from COVID-19,...

When people breathe wildfire smoke, the short-term health effects can range from eye and nasal irritation and coughing to worsening asthma, heart attacks, and strokes....

A review of so-called "smart drug" nutritional supplements found a handful that were packed with foreign pharmaceuticals not approved in the United States, often in potentially...

There was a wide range of accuracy among the tests. Specificity -- the ability to correctly identify those without the disease -- ranged from 82% to 100%...

Fifty-four percent of patients without symptoms tested positive for SARS-CoV-2, as did 64% of those with mild symptoms. There was no significant difference in the viral load...

Investigators found that among bipolar patients who fail to respond to standard treatments, ECT can be a lifesaver, preventing out-of-control mood swings and dramatically...

New research from the National Institutes of Health and other institutions suggests that some people have antibodies that are misguided, called autoantibodies, that attack the...

The announcement clears the way for Florida and other states to implement a program bringing medications across the border to save money. The effort is strongly opposed by...

Young athletes who've had moderate COVID-19 symptoms should be symptom-free for 14 days and get their doctor's OK before returning to practices or games, according to a leading...