Moscow’s exit from the deal generated alarm in a number of populous lower-income countries dependent on Ukrainian grain.

As omicron infections wane, some government leaders are optimistic that COVID-19 is becoming endemic, meaning more predictable and manageable. But many scientists say it’s too soon to tell and warn against easing pandemic restrictions.

It’s been almost a year since the first COVID-19 vaccines were approved, and half of the world is at least partly vaccinated. Now, the emergence of the omicron variant is underscoring the risks of un…

Vaccines are a major public health success story, but the COVID-19 pandemic underscores the many challenges involved in getting a vaccine to everyone who needs it.

Some governments and businesses are starting to use digital and paper passes that certify a person has been immunized against COVID-19, spurring debate over the ethics of vaccine passports.