In one Morbidity and Mortality Weekly Report, the CDC observed Arizona schools that opened without a mask requirement had a 3.5 times more likely to have a COVID outbreak than schools that opened with a school mask requirement.
A @CDCMMWR report looking at schools in two AZ counties found that schools w/o a mask requirement were 3.5 times more likely to have a #COVID19 outbreak than schools that required masks from the start of the school year. More: https://t.co/suuuLNItxJ. pic.twitter.com/P4k7mMqf86— CDC (@CDCgov) September 24, 2021
An additional report exhibits school closures, with the CDC counting almost 2,000 schools shut down during the early part of the current school year. More than 900,000 students in more than 40 states were impacted.
Further, the CDC observed in a third study that pediatric cases in U.S. counties with school mask requirements were half of those in counties without them, covering a time period encompassing the start of the 2021-2022 academic school year.
The studies come several months after the CDC urged districts to continue mask protocols, mainly recommended as COVID vaccines were steadily being approved for younger age groups. Since then, a resurgence of cases had to be taken into account with the highly-contagious delta variant ravaging the country.
CDC tracking data on Friday showed the age groups of 12 to 15 years and 16 to 17 years averaged the most U.S. cases per 100,000 population at 41.3 and 42.8 cases, respectively.