The US has done an about-face on its approach to the coronavirus pandemic this week. Masks are back, vaccine mandates are looming, and officials are sounding more worried than they have in months.

Vaccination was shown to lower risk of developing severe COVID-19 in both variants, with the largest difference in risk observed in patients aged 40 to 59 years. Patients infected with the SARS-CoV-2 ...

First, many called it simply the coronavirus, then COVID or COVID-19. Now, we are keeping track of descriptors like alpha, beta and gamma, the variants of COVID-19. The World Health Organization ...

Pushback is happening over vaccine requirements and mask mandates. The United States is facing a COVID-19 surge this summer as the more contagious delta variant spreads. More than 615,000 Americans ...

Part of the problem is low vaccination rates, experts said. The Centers for Disease Control and Prevention assigned two federal "surge team" members to Missouri this week to help fight the state's ...