OAKLAND (KPIX) — A COVID testing mishap led to a slew of problems for at least three schools within the Oakland Unified School District.

More than a dozen false positive tests, when they should have indicated COVID negative, forced the Alameda County Department of Health to direct at least one classroom at Montera Middle School into full quarantine at home, and possibly more.

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“We’re very regretful it’s happened. As soon as we got some concerns, we started digging into it,” said Oakland Unified School District spokesperson John Sasaki.

According to Oakland Unified School District officials, Vestra Labs conducted rapid antigen tests at school campuses Friday, after other positive tests came to light. It’s unclear how many students or staff at Montera Middle, Montclair Elementary, and Oakland High School were tested overall.

“In addition to the false positives, starting the school year and not having clear information from the district is anxiety provoking,” said Montera Middle School parent Loryn Hudson.

OUSD’s COVID dashboard shows 12 classes throughout the district are in full-quarantine at home.

The district began informing those who received false positives on Tuesday, whether they can come back to class starting Wednesday.

“We are currently working with the state, and county who are looking at what’s going on here. They are working with the testing company as well to ensure that whatever it is that went wrong, doesn’t happen again,” said Sasaki.

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Some parents believe regular testing, like Los Angeles Unified is doing for 500,000 students and staff, is the responsible solution that Oakland should follow.

“If we don’t have prevention it’s going to be a bigger mess,” said Hudson.

The latest COVID alarm forcing classrooms to quarantine at home is yet another incentive for parents and teachers, who don’t want to go back to Zoom school to get vaccinated.

“From the data we have in the U.S. over the last year, the kids are getting it from the parents, so getting vaccinated is the best thing to do,” said UCSF Professor of Infectious Diseases Dr. Peter Chin-Hong.

KPIX-5 reached out to Vestra-Labs, which conducted the rapid-antigen tests to ask what may have gone wrong.

They directed us to the California Department of Health, but there was no response as of Tuesday evening.

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According to the OUSD, the same company conducted follow up PCR tests, which are more reliable than the rapid tests that ended up being false positives.