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.

The variant of the SARS-CoV-2 virus called delta continues to spread rapidly across many parts of the world. What do we know about this variant so far? Share on Pinterest What do scientists know about ...

The alpha variant has been the most prevalent lineage of the novel coronavirus in the United States since April, but the U.S. Centers for Disease Control and Prevention expects that is no longer the ...

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 ...

The delta coronavirus variant surging across the United States appears to cause more severe illness and spread as easily as chickenpox, according to an internal document from the US Centers for ...

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 ...

In a recent study published in Scientific Reports, researchers investigated whether trypsin, a protease, increased severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infectivity. In addition ...

WASHINGTON - In a press briefing Friday, the head of the WHO said the delta variant is "quickly becoming the dominant strain in many countries," and thus, the world is in a "very dangerous period" of ...

We were unable to process your request. Please try again later. If you continue to have this issue please contact customerservice@slackinc.com. The risk for severe disease or death among U.S. adults ...

Some patients "don't think COVID is real," one health care worker told ABC News. Health care workers in southwest Missouri are sounding the alarm over a wave of young, unvaccinated COVID-19 patients ...