CDC MMWR: Association Between K-12 School Mask Policies and School-Associated COVID-19 Outbreaks in Maricopa and Pima Counties, July – August 2021

More evidence was published today in a new CDC MMWR showing that Governor Ducey’s hostility toward universal classroom masking is causing kids to get sick and miss out on in-person learning. Researchers from ASU, CDC and the Maricopa and Pima County health departments found that schools without a mask requirement were 350% more likely to have a COVID-19 outbreak than schools with a mask requirement in place at the start of school year.  

The team examined COVID-19 outbreak data among 999 K-12 public, non-charter schools in Maricopa and Pima Counties during the first six-weeks of the school year from July 15 to August 31, 2021.  After controlling for grade levels, enrollment size, Title 1 status, county school location & COVID-19 community case rates, schools without a mask requirement were 350% more likely to have an outbreak than schools that had a mask requirement in place at the start of the school year.

Among the 999 schools, 21% had a mask requirement when school started, 31% implemented a mask requirement a median of 15 days after school started and 48% had no mask requirement during the entire time period.  

Of the 191 school-associated outbreaks in July and August, almost 60% occurred in schools without a mask requirement. Only 8% occurred in schools with a mask requirement in place at the start of the school year. About 1/3 of outbreaks occurred in schools with mask requirements implemented later in the year.

From the Report:

“In the crude analysis, the odds of a school-associated COVID-19 outbreak in schools with no mask requirement were 3.7 times higher than those in schools with an early mask requirement (odds ratio [OR] = 3.7; 95% CI = 2.2–6.5). After adjusting for potential described confounders, the odds of a school-associated COVID-19 outbreak in schools without a mask requirement were 3.5 times higher than those in schools with an early mask requirement (OR = 3.5; 95% CI = 1.8–6.9).”

“In the two largest Arizona counties, with variable K–12 school masking policies at the onset of the 2021–22 academic year, the odds of a school-associated COVID-19 outbreak were 3.5 times higher in schools with no mask requirement than in those with a mask requirement implemented at the time school started. Lapses in universal masking contribute to COVID-19 outbreaks in school settings; CDC K–12 school guidance recommends multiple prevention strategies. Given the high transmissibility of the SARS-CoV-2 B.1.617.2 (Delta) variant, universal masking, in addition to vaccination of all eligible students, staff members, and faculty and implementation of other prevention measures, remains essential to COVID-19 prevention in K–12 settings.”

Fortunately, courageous school districts have challenged the constitutionality of Governor Ducey’s prohibition of universal masking requirements in public schools, scheduled to kick in next Wednesday. Judge Katherine Cooper from the Maricopa County Superior Court heard the lawsuit filed by a coalition of organizations including the Arizona School Boards Association, the Children’s Action Alliance, the Arizona Education Association, and the Arizona Advocacy Network See the Complaint.

The suit asks the court for Injunctive Relief on the portions of the health and K-12 budget bills that prohibit school districts from implementing universal masking policies. The action rightly points out that the legislature passed, and the governor signed three budget bills (HB 2898, SB 1824, and SB 1825) that “… include substantive policy provisions that have nothing to do with the budget” in direct violation of the state constitution.

Regardless of how Cooper rules in the coming days, the case will be quickly appealed to the Arizona Supreme Court. I expect a Preliminary Injunction stopping the implementation of Ducey’s harmful policy will be issued pending a final ruling on the merits of the case.

The case has far-reaching implications. If the court holds that the Budget Bills were unconstitutional because they violate the single subject requirement, then those aspects of the BRB that pertain to the case will need to be excised.

The court could even rule that the budget reconciliation bills (BRBs) are unconstitutional in their entirety, which would result in a special legislative session to draw up a new state budget for 2022.

It’s too bad that we’re stuck with a Governor that is so hostile to science and who cares so little about whether kids are safe and have a chance at in-person learning.