COVID schools report from researchers in Washington looks at hybrid K-5 class model
A COVID-19 schools report from researchers in Washington state has simulated the risk of COVID-19 infection if students return to in-person learning in different scenarios, including a hybrid class model for elementary school students.
The report, released Friday by the Washington State Department of Health and Public Health – Seattle & King County, suggests providing elementary students with some in-person classes first when transmission levels decrease.
“Return to in-person learning will pose significant risks for students, staff and teachers,” the report says. “However, our results suggest that, depending on the incidence of COVID-19 in the community, a carefully organized incremental approach that returns the youngest students first with a reduced schedule would minimize the risk of infection within schools and provide important benefits to the neediest children.”
The report was done by the Institute for Disease Modeling, and looked at King County demographics to simulate what might happen if schools returned for in-person classes (given a reproductive number of 0.9) in an area with 20 cases per 100,000 people over 14 days, an area with 50 cases, and an area with 110 cases.
“What we have found is that there is no ‘zero-risk’ scenario for resuming in-person instruction in Washington state schools,” Jamie Cohen, a co-author of the report, said in a state Department of Health press release. “But our analysis shows that there are pathways to resuming limited and carefully monitored in-person instruction for younger students. This can happen only if everyone works together to minimize disease transmission in their local communities.”
According to the report, in places with 110 cases per 100,000 that resume in-person classes without safety measures, “17.2 percent of students and 24.2 percent of teachers and staff could attend school while infectious,” the press release said.
With measures such as masks, social distancing, hand washing, screening for symptoms, placing students in cohorts, and contact tracing, “up to 4.1 percent of students and 5.5 percent of teachers could still be infected between September 1 and December 1 if community incidence is high,” the release said.
With a hybrid plan the report considered just for elementary schoolers in areas with 20 cases per 100,000, “the percentage of students infected between September 1 and December 1 could be as low as 0.1 percent, and the percentage of teachers and staff infected could be as low as 0.2 percent.”
The report itself explains: “An approach with only elementary schools returning to in-person on an A/B 2-day a week schedule, while other schools remain remote, would reduce the cumulative risk of COVID infection in students, staff and teachers in school to below 1.2 percent in the first three months of school, depending upon the community-wide COVID incidence rate in the two weeks prior to school reopening.”
It goes on to note: “These reopening strategies come at an educational cost, requiring students to spend up to 83 percent of school days at home, either through scheduled distance learning or due to infection-related quarantine.”
The report follows another one from IDM in July.
“Previously we modeled only students and teachers within schools, but here we have added in non-teaching staff to more accurately capture contact structures and disease transmission within schools,” the new report says. “We are also more accurately capturing the scheduling dynamics of schools.”
Dan Klein with IDM said at a virtual press conference Friday that the new report doesn’t factor in increased transmission from parents going back to work as kids return to school, and that it assumes on remote learning days students are home, not in some other “congregate care setting.”
He also noted: “We don’t fully understand how susceptible kids are, how infectious they are.”
Asked by a reporter how applicable the results are outside of King County, he said: “Broadly, I would encourage sort of roughly looking at these, with the understanding that there are some King County specific things here. Perhaps rural populations with different employment rates and different age structures, the results might be slightly less generalize-able.”
Gov. Jay Inslee and Superintendent of Public Instruction Chris Reykdal have said distance learning is strongly recommended, but not mandated, for schools in high-risk counties, meaning places that have more than 75 cases per 100,000 people during a two-week period.
Lacy Fehrenbach, deputy secretary for COVID-19 response at the Department of Health, said in the press release: “The report supports our guidance that full in-person learning is not wise right now given current COVID-19 transmission levels in most Washington communities. However, it is possible to resume some in-person learning for the children who need it most if we work to reduce the spread of COVID-19 in our communities.”
Fehrenbach noted at the press conference that most counties in the state still have more than 75 cases per 100,000.
“Stay with us on wearing masks, watching your distance, and having fewer, safer and shorter interactions with others,” she said.
This story was originally published August 14, 2020 at 10:43 AM.
