Amid Delta, CDC strengthens COVID-19 mask guidance

The Centers for Disease Control and Prevention (CDC) today strengthened mask recommendations once again, suggesting even vaccinated people in areas seeing high virus activity should resume wearing masks indoors.

Also, all schoolchildren, staff, and teachers should now wear masks when indoors, regardless of vaccination status, when the 2021-22 school year begins next month, the agency said.

The about-face comes 2 months after the agency said fully vaccinated Americans could ditch their masks and return to normal. But new data on breakthrough infections in vaccinated Americans caused by the Delta (B1617.2) variant shows in rare cases, vaccinated people can transmit the virus, necessitating mask use in some instances.

"We have always said our guidance and recommendations will follow the science, and today we have new science related to the Delta variant," said CDC Director Rochelle Walensky, MD, MPH, during a press call.

"Recent outbreak investigations shows the variant behaves uniquely and differently from past strains of the virus, and indicates that in rare occasions some vaccinated people infected may be contagious. This new science is worrisome."

Cases increased 300% in July

Eight in 10 sequenced virus samples in this country are now caused by the Delta variant, which is at least 50% more transmissible than the wild-type virus.

The CDC said between Jun 19 and July 23, COVID-19 cases increased about 300% nationally, followed by increases in hospitalizations and deaths, driven by the Delta variant. Also, vaccine uptake has slowed nationally, with wide variation in coverage by state (3.9% to 67.2%).

"Until vaccination coverage is high and community transmission is low, public health practitioners, as well as schools, businesses, and institutions (organizations) need to regularly assess the need for prevention strategies to avoid stressing health care capacity and imperiling adequate care for both COVID-19 and other non–COVID-19 conditions," the CDC said.

Local decision making about masks should hinge on five factors: 1) level of SARS-CoV-2 community transmission; 2) health system capacity; 3) COVID-19 vaccination coverage; 4) capacity for early detection of increases in COVID-19 cases; and 5) populations at increased risk for severe outcomes from COVID-19, the CDC said.

Walensky said the decision weighed heavily on her, but her goal was to facilitate children back in classrooms and to stop continued sickness and death from COVID-19. She said earlier this summer, the CDC had been more hopeful more Americans would be vaccinated, and she now believes that children under 11 will not be eligible for vaccination before school starts in the next month.

Late last week, the Food and Drug Administration asked Pfizer and Moderna to increase the size of their vaccine studies in children 5 to 11 years old to 3,000, up from 1,000, to better detect any side effects, according to the Wall Street Journal. Experts say it could be this winter before the vaccine is approved for use in that age group.

"I know this is frustrating," Walensky said. "But this is still largely a pandemic of the unvaccinated."

Though breakthrough infections can occur in vaccinated Americans, Walensky emphasized that all three vaccines in use in the United States are very effective in preventing severe illness and death from the Delta variant.

The United States reported 89,418 new COVID-19 cases yesterday, and 61 deaths, according to the Johns Hopkins COVID-19 tracker, and the 7-day average of new daily COVID-19 cases is 55,986, according to the Washington Post tracker.

The CDC COVID Data tracker shows that 395,460,845 COVID-19 vaccine doses have been delivered in the United States, and 342,607,540 have been administered, with 49.2% of Americans fully vaccinated and 56.9% with at least one dose.

More cities reinstate mask mandates

Savannah, Georgia, became the latest state to reinstate a mask mandate for all residents due to rising local cases of COVID-19. The mandate started yesterday and goes through Aug 25.

Also yesterday, New York City Mayor Bill DeBlasio announced that all city workers would have to get vaccinated or be tested weekly for the coronavirus, NPR reports. California Gov. Gavin Newsom declared a similar policy for state employees and healthcare workers.  

Elsewhere, hot spots are reporting surges of activity. Texas reported 4,320 COVID-19–related hospitalizations Saturday, a high not seen since mid-March, according to Fox News, and the mayor of Orange County, Florida, home to Disney World, said yesterday that the county is now in "crisis mode" as it grapples with nearly 1,000 new cases a day, CNN reports.

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