Some Americans who received the Covid-19 vaccine earlier this year are hearing surprising and relatively rare news: They’ve tested positive for the coronavirus. These so-called breakthrough cases are ...

The Centers for Disease Control and Prevention listed the COVID-19 delta variant as one of its "variants of concern" (VOCs) on June 15. According to the CDC, VOCs can be more contagious, more ...

The Centers for Disease Control and Prevention listed the COVID-19 delta variant as one of its "variants of concern" (VOCs) on June 15. According to the CDC, VOCs can be more contagious, more ...

The delta variant is fueling the COVID-19 surge in the United States, but experts warn that a more dangerous variant could emerge if more Americans don't get vaccinated. Delta is the most recent of ...

OBJECTIVESTo evaluate the effectiveness of the mRNA-1273 vaccine against SARS-CoV-2 variants and assess its effectiveness against the delta variant by time since vaccination. DESIGNTest negative ...

While the delta COVID-19 variant is the dominant strain in the U.S., it’s now officially the dominant strain worldwide “by far,” officials from the World Health Organization said during a Sept. 21 ...

"It's the biggest experiment that's ever happened." In a stunningly short period of time, the delta variant has changed the course of the COVID-19 pandemic by evolving to become more transmissible ...

Estimates show the variant accounts for over 51% of all new cases nationwide. A highly contagious variant of the novel coronavirus that was initially identified in India is now the dominant strain in ...

While the Biden administration plays for time, some lawmakers believe sanctions would be the faster route to establishing whether the origin of covid-19 was a lab-leak in Wuhan, China. Image: Roman ...