ABC Science Collaborative highlights issues with CDC schools guidance
ABCSC document is for "superintendents to facilitate safe and data-driven school reopening"
A new report by the ABC Science Collaborative (ABCSC) aimed at helping district superintendents navigate recent CDC school opening guidance also elaborates on and, in some areas, criticizes the limitations of that guidance.
The ABCSC document made the rounds on Twitter and was tweeted by Dr. Tracy Høeg, a Physician Scientist with a Ph.D. in Epidemiology:


In a tweet following the document, Høeg wrote “And this begs the question: what science is the CDC using to make its guidelines and who are the experts they are consulting? (The more I think about this & the more physician scientists I get to know in this space who disagree with the CDC, the more disturbing this is to me).”
One area singled out that deserves more attention is masking and impact on the six-foot rule for social distancing. The ABCSC report says that in schools where you can mask over 90%, distancing of three feet instead of six should be allowable. Later on in the document, the distancing topic is revisited, noting 6 feet is not a mandate and not always feasible.
Five main points from the report that "summarize the limitations of the CDC Operational Strategy" are below:
On the diagnostic testing mentioned in item five above, ABCSC underscored that while testing can be valuable, such testing "has not been shown to be beneficial or cost-effective in maintaining a safe school environment,” where mitigation strategies are employed. It’s worth noting that the N.C. Department of Health and Human Services (NCDHHS) announced last week it was expanding its COVID-19 testing pilot in K-12 schools and that a state board of education member questioned the expansion of testing given education staffer vaccinations were underway.
Another key area discussed is the use of community transmission rates to keep schools closed.
CDC’s operational strategy guidance advises on the thresholds for community transmission, which in turn are used as “a first step in deciding if full in-person, hybrid, or remote instruction is most appropriate for elementary, middle, and high school level learning.”
The CDC’s guidance page includes a community transmission threshold chart:
The color codes for transmission are Blue (low) Yellow (moderate) Orange (High) Red (Critical). Per the CDC, those levels are defined as “total new cases per 100,000 persons in the past 7 days (low, 0-9; moderate, 10-49; substantial, 50-99; high, ≥100) and percentage of positive tests in the past 7 days (low, <5%; moderate, 5-7.9%; substantial, 8-9.9%; high, ≥10%).”
The Biden Administration’s Dept. of Education Secretary Miguel Cardona has integrated the CDC’s community transmission levels into its newly released “ED COVID-19 Handbook Volume 1: Strategies for Safely Reopening Elementary and Secondary Schools.” Cardona promises to “release additional volumes within the Handbook providing specific strategies to address the extraordinary disruption created by COVID-1.”
The ABCSC’s report counters reliance on this kind of community transmission data, stating that "Community transmission has extremely limited scientific merit and no school-based, individual-risk data to support it.”
Since last fall, Gov. Roy Cooper and NCDHHS Secretary Mandy Cohen have both highlighted the use of a color-coded community transmission chart. Many districts have been pointing to their counties under this color-coded system as a reason for staying in remote instruction.
NC's color-coded county transmission map does not appear to even include “Blue/low transmission” as an option.