Irina Anghel Bloomberg

Coronavirus loses most of its ability to infect shortly after being exhaled and is less likely to be contagious at longer distances, a study from the University of Bristol's Aerosol Research Centre showed.

European Union regulators warned that frequent Covid-19 booster shots could adversely affect the immune system and may not be feasible.

Omicron is once again making people think twice before reaching out for their colorful, reusable cloth face masks.

Most people hospitalized with Covid-19 who emerged with lingering symptoms from the infection showed little improvement a year later, according to a study seeking to assess the effect of long Covid.

The rare form of heart inflammation some people get after a Covid shot occurs far less often in response to vaccination than after the disease itself, according to the largest study to date on the topic.

The World Health Organization said the omicron variant of the coronavirus may change the course of the pandemic. It called on countries to vaccinate as fast as possible and keep measures in place to protect people from infection.

Mixing other vaccines with those from AstraZeneca Plc or Pfizer Inc. offers at least as effective protection against Covid-19 as giving two doses of the same shots, a UK study found.

A U.K. study testing seven different Covid-19 vaccines as booster doses found most of them increased antibodies, with shots from Moderna Inc. and the Pfizer Inc.-BioNTech SE partnership performing best.

Coronavirus loses most of its ability to infect shortly after being exhaled and is less likely to be contagious at longer distances, a study from the University of Bristol's Aerosol Research Centre showed.

European Union regulators warned that frequent Covid-19 booster shots could adversely affect the immune system and may not be feasible.

Omicron is once again making people think twice before reaching out for their colorful, reusable cloth face masks.

Most people hospitalized with Covid-19 who emerged with lingering symptoms from the infection showed little improvement a year later, according to a study seeking to assess the effect of long Covid.

The rare form of heart inflammation some people get after a Covid shot occurs far less often in response to vaccination than after the disease itself, according to the largest study to date on the topic.

The World Health Organization said the omicron variant of the coronavirus may change the course of the pandemic. It called on countries to vaccinate as fast as possible and keep measures in place to protect people from infection.

Mixing other vaccines with those from AstraZeneca Plc or Pfizer Inc. offers at least as effective protection against Covid-19 as giving two doses of the same shots, a UK study found.

A U.K. study testing seven different Covid-19 vaccines as booster doses found most of them increased antibodies, with shots from Moderna Inc. and the Pfizer Inc.-BioNTech SE partnership performing best.