Vaccination is not enough by itself to stop the spread of variants, study finds

Vaccination alone won't stop the rise of new variants and in fact could push the evolution of strains that evade their protection, researchers warned Friday.

They said people need to wear masks and take other steps to prevent spread until almost everyone in a population has been vaccinated.

Their findings, published in Nature Scientific Reports, support an unpopular decision by the US Centers for Disease Control and Prevention to advise even fully vaccinated people to start wearing masks again in areas of sustained or high transmission.

"We found that a fast...