Walensky is a professor at Harvard Medical School and served as the 19th director of the Centers for Disease Control and Prevention. Once clinical trials showed that Covid-19 vaccines were safe and ...

Soon after SARS-CoV-2 began its assault on the world, scientists began searching for clues about what, if any, factors made people more or less likely to get infected with the virus, and more or less ...

Since May, highly contagious "FLiRT" coronavirus variants – a term for new mutations of Omicron – have been driving a rise in infections and emergency room trips. Virus levels at local wastewater ...