NEW YORK -- As Americans brace for the possibility of another difficult winter ahead in the nation's fight against coronavirus, there is a renewed sense of urgency to get as many people inoculated and ...

The Covid-19 vaccines continue to offer strong protection against severe illness and hospitalization, according to research on more than 1 million people published Wednesday in The Lancet Infectious ...

Examining who experiences rare breakthrough COVID-19 infections after vaccination can help improve our understanding of who is vulnerable and whether variants are at play, but these thorough ...

This story first appeared at ProPublica. ProPublica is a Pulitzer Prize-winning investigative newsroom. Sign up for The Big Story newsletter to receive stories like this one in your inbox. Meggan ...

Two health care workers get COVID-19 vaccinations on the same day. Both show strong antibody responses initially, but six months later one stays healthy while the other contracts the virus. A new ...

As measles spreads across the U.S., a few fully vaccinated people have contracted rare breakthrough cases. Here's what to know and why vaccination is still important.