(RxWiki News) Fully vaccinated against COVID-19? You may still need to wear a mask in some settings.
That's because officials with the Centers for Disease Control and Prevention (CDC) made new recommendations about mask-wearing based on new data about COVID-19.
The CDC is now recommending that, in areas where high COVID-19 transmission is occurring, everyone wear a mask when indoors in public places. That includes those who are fully vaccinated.
Why this sudden change? There are two key reasons. The Delta variant of COVID-19 is surging in most parts of the United States, and new data suggests that even vaccinated people can carry high viral loads and transmit the virus to others.
"High viral loads suggest an increased risk of transmission and raised concern that, unlike with other variants, vaccinated people infected with Delta can transmit the virus," said CDC Director Dr. Rochelle P. Walensky in a press release. "This finding is concerning and was a pivotal discovery leading to CDC’s updated mask recommendation. The masking recommendation was updated to ensure the vaccinated public would not unknowingly transmit virus to others, including their unvaccinated or immunocompromised loved ones."
The research that led to this new mask recommendation centered on an outbreak that occurred in Massachusetts. Large public events in the state led to a COVID-19 outbreak that caused 469 cases. Of the people who became sick, 74 percent were fully vaccinated. No deaths were reported from the outbreak, but five patients were hospitalized. The Delta variant was identified in 90 percent of the cases.
Researchers measured the viral loads of those who became infected in the outbreak. The viral loads were similar in vaccinated and unvaccinated patients, the research found.
While breakthrough infections — those that occur in fully vaccinated people — can and do occur, vaccination remains the most effective way to prevent severe illness and death from COVID-19. The vast majority of patients hospitalized for COVID-19 are unvaccinated.
If you have questions or concerns about COVID-19, face masks or COVID-19 vaccines, reach out to your health care provider.
The research that informed the new mask guidance was published in the Morbidity and Mortality Weekly Report.
Report authors disclosed grants from the CDC, National Institutes of Health and Community Tracing Collaborative. No other funding sources or potential conflicts of interest were disclosed.
