BRENTWOOD (CBS SF/BCN) — The Brentwood Union School District reported at least a dozen cases of COVID-19 among students and staff at the district’s 11 schools on Monday morning, days after the district returned to in-person learning.

“This does not mean that students and staff contracted COVID at school,” district superintendent Dana Eaton said. “We do not currently have any cases where contact tracing has shown that anyone has contracted COVID at school from a positive individual.”

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Eaton said the Contra Costa Health Department told the district it should expect positive cases. As of Monday morning, those showing symptoms and those exposed to COVID have not been tested positive for the virus — yet.

“The positivity rate at schools is likely to mirror that of the communities they reside in,” Eaton said. “Currently, there have been 205 positive cases in Brentwood over the past 14 days, so it is expected that the schools will have cases.”

Health officials told the Contra Costa County Board of Supervisors last week the delta variant is now the dominant strain in the county. The virus has re-surged in the county, with four times as many new hospitalizations reported in July than June. More than 99 percent of deaths in Contra Costa since vaccines became available have been among the unvaccinated.

Eaton said the district is following state safety guidance and requiring masks indoors, regardless of vaccination status. Officials are also stressing hand washing, cleaning and sanitation protocols.

Andrea Erwin says she’s concerned about the 2 positive COVID cases at Garin Elementary where her 7-year-old son goes to school.

“I’m nervous. I honestly did not want to send my son to school this morning. He’s not vaccinated. It puts him at risk.”

While others said COVID cases were bound to pop up.

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“I know they’re doing the best they can and being back in school was kind of our top priority,” said one parent.

“The benefit of being in school and having the interaction, I think, is on a much higher scale than the worry I would be for them to possibly contact it here,” said another.

Eaton said students will remain in school.

“There is no legislation that currently allows schools to return to hybrid or distance learning,” he said. “Schools are expected by the state to offer full-time in-person instruction and follow the (state’s) guidance to keep students and staff safe.”

The district has a lengthy checklist of steps to take once word of a positive case comes in, including notifying district leadership and a school’s nursing team. Contact tracing is done, and families are notified. Affected classrooms are cleaned. The district also publishes a dashboard of all known cases on its website.

“We are very happy to be back in school full-time,” Eaton said. “We want to do everything we can to keep it that way.”

Katie Nielsen contributed to this report.

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