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.

The Delta variant is driving new COVID-19 surges, even as countries around the world make gradual progress in vaccinating their populations. Five graphics show how the strain is taking over and who’s…

As COVID-19 continues to ravage countries including Brazil and India, scientists warn that cases and deaths are being undercounted. Without accurate tallies, government responses won’t be enough to d…

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.

Several countries stand out for their success in delivering coronavirus vaccinations, while most of the world is struggling to figure out how to get immunizations into more arms.