Covid-19’s Delta variant is proliferating world-wide threatening unvaccinated populations and economic recovery. WSJ breaks down events in key countries to explain why Delta spreads faster than ...

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 ...

As 56 million school children return to the classroom, the debate over masks in school rages -- along with the Delta variant. "The Delta variant is really effective at making copies of itself," says ...

Since the CDC limits data reporting on breakthrough COVID-19 infections — those occurring among fully vaccinated people — to those that cause severe disease, mild or asymptomatic infections caused by ...

ATLANTA, Ga. — The delta variant that’s now the dominant strain of coronavirus in the U.S. appears to be as transmissible as chickenpox, according to an internal document from the Centers for Disease ...

Differing strains of the coronavirus continue to appear around the world and a new COVID-19 variant, the so-called "Delta" variant, has health experts concerned. The variant, otherwise known as B.1617 ...

COVID-19 cases have been surging in Texas and nationally - mostly among unvaccinated people - as the highly contagious delta variant has become dominant. While dozens of variants have spawned from the ...