SANTA CRUZ COUNTY (CBS SF) – Dozens of inmates at the Santa Cruz County Jail have been placed into quarantine protocols due to a COVID-19 outbreak at the facility.

“This is the most significant outbreak in our jail since the start of the pandemic,” the Santa Cruz County Sheriff’s Office announced Monday.

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According to the sheriff’s office, about 12 inmates out of nearly 300 tested positive at the main jail on Friday. Another 35-40 inmates were exposed and are under quarantine protocols.

Cases were detected during routine testing, deputies said. The source of the outbreak is under investigation and contact tracing is underway.

“We are committed to ensuring the safety of all 279 inmates at the main jail as well as our staff,” the sheriff’s office said in a statement.

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Inmates who tested positive are either asymptomatic or have mild symptoms. They are being isolated and monitored by medical staff, deputies said.

People brought into the jail undergo both a rapid and PCR test for COVID-19 and are quarantined until testing negative, according to the sheriff’s office. Inmates are also offered the COVID-19 vaccine and are provided masks, cleaning materials and are encouraged to physically distance.

Meanwhile, correctional officers must undergo testing protocols and wear masks throughout their shifts. In August, the county mandated all of its employees to be vaccinated against COVID-19 or undergo weekly testing.

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As of November 8, about 67.5% of all county residents were fully vaccinated, according to the Santa Cruz County Health Services Agency.