WASHINGTON, D.C. — As the omicron variant sweeps across the nation, prompting long lines at COVID testing sites, there is a small silver lining: there are fewer hospitalizations and deaths from ...

The pandemic has brought many tricky terms and ideas from epidemiology into everyone’s lives. Two particularly complicated concepts are vaccine efficacy and effectiveness. These are not the same thing ...

PHILADELPHIA -- Americans face at least two weeks of uncertainty before major questions may get answered about the omicron variant of the coronavirus. Health experts urge the public to be cautious and ...