DAVIS (CBS13) – Kids are back in class with safety protocols like physical distancing, masking, and plastic barriers throughout classrooms. Even so, newly developed surveillance swabbing detected the coronavirus in HEPA filters in two Davis classrooms in the last two weeks: one at Korematsu Elementary and the other at North Davis Elementary.

“That’s really scary, but I’m glad they can trace it back,” said one parent.

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The testing is part of a pilot program started last week with Davis Joint Unified School District and Healthy Davis Together, with UC Davis conducting the testing. The goal of the system is to identify a problem before it can spread.

“It’s basically providing passive testing in place of each child getting tested every single day because it’s monitoring any viral activity in the whole room,” said Dr. Sheri Belafsky.

Belafsky is the medical director for Healthy Davis Together and she oversees medical surveillance for UC Davis Public Health. She says students have been tested and no coronavirus has been detected. How is that possible?

“From the time the swab was collected and processed in the lab, the results found and children tested, there is a period of several days and that person’s infection could be waning,” she said.

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She said all HEPA filters that tested positive were replaced and those have since tested negative. More proof the threat is gone. That’s good news for parents who know with kids, the fight against the spread of the coronavirus is a daily battle.

“They end up being close at lunch with no masks. It’s hard for kids to keep their mask on.”

Belafsky says district staff will continue to swab classroom filters weekly.

“By having an air filter in place and swabbing, we basically have a sentinel,” she said.

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The district is reminding parents to sign waivers so their children can immediately be tested if this is an issue again. This type of HEPA swabbing has been done in hospitals, but not schools. They plan to expand this pilot program to include wastewater monitoring in the coming months.