MARIN COUNTY, Calif. (KGO) -- As students return to the classroom after winter break, school districts are beginning to see the results of at-home COVID-19 tests that students and staff took following the holidays.
At one school district in Marin County, 81 students and 16 staff across just three schools are out this week due to COVID. Even the superintendent tested positive and is staying home in isolation.
"Over the break we saw a dramatic surge in omicron," Marin County's public health director Dr. Matt Willis told ABC7 News.
The Larkspur Corte Madera School District is made up of just three schools: a middle school and two elementary schools. When classes returned on Monday, the district said nearly 6% of students were out because of a positive COVID-19 test. That is roughly double the district's usual daily absence rate.
"On January 3, which was our first day back, we had 81 students out due to COVID-19 and 16 staff due to COVID-19," Superintendent Dr. Brett Geithman said on Tuesday.
Dr. Geithman said he tested positive on December 29 after developing mild symptoms, but the county says many of the positive cases have been from people who are asymptomatic.
"The vast majority are not having symptoms," Dr. Willis said.
Marin County is one of many Bay Area counties that encouraged students and staff to take a COVID-19 test before returning to class this week. The county distributed roughly 100,000 tests. As results start coming in, it's giving health officials a better picture of just how widespread the virus is.
"We have about 25,000 results now coming in and about 700 have been positive," Dr. Willis said on Tuesday afternoon. "So, it's a significant, significant number of people who have been found to be infected through that testing."
He said he's not surprised by school districts that have seen a high positivity rate.
"It really validates the reason we're doing this in the first place," he said, "To make sure people who are coming back positive are not coming back to school on that first day."
Dr. Geithman said parents should not be concerned by the high number of positive cases.
"School based transmissions are extraordinarily low," he explained. "School is a safe place to be."
The larger concern for Dr. Willis is making sure schools have the staff and infrastructure to stay open if people continue to test positive.
"Staffing shortages might actually threaten schools more than cases," Dr. Willis said.
To reduce transmission even further, Dr. Willis said Marin County will be temporarily prohibiting indoor gatherings, such as assemblies, at schools, such as assemblies. And prohibiting spectators, including parents, at indoor school sporting events.
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