BERKELEY, Calif. (KGO) — Berkeley High School reportedly sent out a warning following a possible exposure to mumps on campus.
Parents were notified by the principal and city health department that staff, parents and students who were at the school on February 2 may have been exposed, according to the Berkeleyside.
The city’s health department is now investigating.
Berkeleyside also reported that there was also an exposure at Sylvia Mendez Elementary on Jan. 14 and Jan. 15.
“All evidence indicates that this mumps exposure is contained within a single household unit with incomplete Mumps vaccination status which had exposure to mumps outside of California during the winter holiday,” the letter obtained by Berkeleyside said. “There is no evidence of community transmission of Mumps in City of Berkeley.”
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“If you or your child are susceptible and were exposed to mumps infection at Berkeley High School, symptoms may develop between 2/14/2026 – 2/27/2026. Earlier exposure at Sylvia Mendez Elementary School occurring around the winter holidays has been resolved, and the exposure window for Sylvia Mendez Elementary has closed,” the letter said.
The Centers for Disease Control and Prevention says there were 348 cases of mumps reported across the country in 2025.
The possible exposure comes as the U.S. vaccination rates have dropped among children with exemptions reaching an all-time high.
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