New CDC Guidelines Recommend Vaccinated Individuals Wear Masks Indoors in Areas With High Rates of Transmission

Officials with the CDC updated their COVID-19 guidelines today, urging that vaccinated individuals in areas of substantial and high transmission wear masks in public indoor spaces, including schools, in order to prevent the spread of the Delta variant.¹

“This pandemic continues to pose a serious threat to the health of all Americans,” said Rochelle P. Walensky, MD, MPH, director of the CDC, in a press briefing. “I have said throughout my tenure at the CDC that our guidance and recommendations will follow the science in our efforts to protect the health of as many Americans as possible, and today we have new science related to the Delta variant that requires us to update the guidance regarding what you can do when you are fully vaccinated.”¹

The CDC recommends that all individuals in K-12 schools wear a mask indoors, including teachers, staff, students, and visitors, regardless of vaccination status. Further, the organization urged community leaders in areas of high transmission to encourage vaccination and universal masking in order to help prevent the spread of the Delta variant.¹

“This week, our data show that Delta remains the predominant variant circulating in the United States,” Walensky said in the briefing. “Eight in 10 sequenced samples contains the Delta variant. In recent days, I have seen new scientific data from recent outbreak investigations showing that the Delta variant behaves uniquely differently from past strains of the virus that cause COVID-19.”¹

According to the CDC, recent data suggest that in rare occasions, vaccinated individuals infected with the Delta variant after vaccination may be contagious and spread the virus to others; however, there is a greater risk of infection from unvaccinated individuals. Walensky urged all unvaccinated individuals to get vaccinated and continue wearing a mask in public spaces until they do so.¹

“Getting vaccinated continues to prevent severe illness, hospitalization, and death, even from Delta,” Walensky said in the briefing. “It also helps reduce the spread of the virus in our communities. Vaccinated individuals continue to represent a very small amount of transmission occurring around the country. We continue to estimate that the risk of a breakthrough infection with symptoms upon exposure to the Delta variant is reduced by 7-fold. The reduction is 20-fold for hospitalizations and death.”¹

Officials with the Infectious Disease Society of America (IDSA) released a statement in support of the new guidelines, citing statistics underlining the low rates of vaccination throughout the United States. Vaccination coverage is below 40% in more than half of the counties in the country, and 63% of US counties have high or substantial virus spread, according to data from the CDC.²

“While COVID-19 vaccines currently in use in the United States are highly effective against the Delta variant in preventing serious illness and death, they do not eliminate the possibility that vaccinated people might spread the virus to others,” said IDSA President Barbara D. Alexander, MD, MHS, FIDSA,in a press release. “The overwhelming majority of current COVID-19 cases are occurring in unvaccinated individuals, and significantly increasing vaccination rates are urgently needed to stop the spread of COVID-19 and save lives. Until then, mask wearing will help reduce infections, prevent serious illnesses and death, limit strain on local hospitals and stave off the development of even more troubling variants.”²

REFERENCES

• CDC media telebriefing: Update on COVID-19. CDC; July 27, 2021. Accessed July 27, 2021.
• IDSA supports new CDC guidance on mask wearing as Delta variant spreads [news release]. IDSA; July 27, 2021. Accessed July 27, 2021. https://www.idsociety.org/news--publications-new/articles/2021/idsa-supports-new-cdc-guidance-on-mask-wearing-as-delta-variant-spreads/