Story at a glance
- The CDC announced fully vaccinated people should wear masks in some public indoor places.
- CDC Director Rochelle Walensky explained that wearing masks will stem transmission in unvaccinated communities.
- Reducing virus transmission will help stop contagious strains from developing, experts say.
The U.S. Centers for Disease Control and Prevention (CDC) announced changes Tuesday to its mask guidance, recommending that fully vaccinated adults wear masks in indoor public spaces in communities with high COVID-19 transmission rates. The new guidance comes as public health officials become increasingly worried about coronavirus mutations.
“The big concern is that the next variant that might emerge, just a few mutations potentially away, could potentially evade our vaccines,” CDC Director Rochelle Walensky said during a press call.
The recommendation stems from the surge of new infections driven by the delta variant within unvaccinated populations.
Specifically, Walensky said that the renewed guidance aims at preventing more transmissible strains from developing as the virus multiples and spreads.
“The largest concern that I think we in public health and science are worried about, is...the potential mutations away we are from a very transmissible virus that has the potential to evade our vaccines in terms of how it protects us from severe disease and death,” Walensky said.
She noted that the U.S.'s situation with the virus has not reached this point and that the vaccines currently approved work “really well” in preventing a COVID-19 infection.
The delta variant — now the most prominent strain in the country, per Walensky — is more contagious than the original COVID-19 strain, with some studies estimating that a person sick with the delta variant can have 1,000 times the amount of the viral load seen in previous strains.
Wearing masks, despite an individual’s vaccination status, can help prevent the virus from spreading and therefore halt any mutations that may become even more contagious than ones like the delta variant, experts say.