Science

The Centers for Disease Control and Prevention recommended Tuesday that fully vaccinated Americans in parts of the country with "substantial or high transmission" of COVID-19 should return to wearing masks indoors, citing new data on the highly contagious Delta...

Delta has changed the course of the pandemic in the United States yet again. After spurring a summer surge in COVID-19 cases, the more transmissible coronavirus variant is now driving federal health officials’ decision to recommend that everyone, regardless of...

Wilson Montoya immigrated to New York from Colombia and went to college to become a social worker helping vulnerable people in his community. But like many others, in order to make that dream possible, Wilson was left with $70,000...

The inside of a shark is full of curiosities, starting with rows of hardworking teeth that can be replaced by fresh ones throughout its life. But quite a bit farther down the digestive tract — in fact, right before...

A Russian Progress cargo ship undocked from the International Space Station early Monday, taking with it the two-decades-old Pirs airlock and docking compartment to clear the way for Thursday's arrival of Russia's new Nauka multipurpose lab module. ...

Of the 39 percent of adults who are unvaccinated, about half say they are completely unwilling. But even within that group, some say they would comply if required to do so.Understand the State of Vaccine Mandates in the U.S.Some...

Over the last decade, Dr. Mercola has built a vast operation to push natural health cures, disseminate anti-vaccination content and profit from all of it, said researchers who have studied his network. In 2017, he filed an affidavit claiming...

More and more hospitals and major health systems are requiring employees to get the Covid-19 vaccine, citing rising caseloads fueled by the Delta variant and stubbornly low vaccination rates in their communities and even within their work force.Many hospitals...

Even though COVID-19 vaccines are more than 90% effective at preventing serious illness, millions of vaccinated people will likely have a breakthrough infection, according to the Centers for Disease Control and Prevention. Most of the cases...

People with weak immune systems don’t always mount strong defenses against the coronavirus, even after being fully vaccinated. A third COVID-19 vaccine dose might help protect some immunocompromised people, evidence suggests. But for now, there’s not enough data to...