TRAVIS AFB (CBS SF) — Federal health officials confirmed Wednesday that a total of 12 patients evacuated from the Diamond Princess cruise ship and flown to Travis Air Force Base have been isolated at Bay Area hospitals after displaying possible coronavirus symptoms.

The patients had been flown to Travis AFB from Japan over the weekend, where they were under quarantine on the cruise ship. While six patients exhibiting symptoms consistent with possible coronavirus infection were transported to the University of Nebraska Medical Center, the new information from the Centers for Disease Control and Prevention confirmed that an additional 12 patients were also being isolated and treated at Northern California hospitals.

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Napa health officials on Tuesday said they were treating one cruise ship evacuee with a confirmed case of coronavirus, but the CDC maintained on Wednesday that the 12 cases from the Diamond Princess currently under observation at hospitals in the region were displaying symptoms consistent with exposure to coronavirus and not confirmed.

CDC spokesman Jason McDonald said that the person identified as testing positive was tested by the health officials in Japan, but so far the CDC has not confirmed any new cases.

Two patients of the 12 patients are currently at Queen of the Valley Medical Center in Napa.

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“There is minimal risk for Napa County residents from the arrival of these two patients at the Queen of the Valley,” said Napa County Public Health Officer Karen Relucio in a press release. “They are in isolation, and are receiving medical care and undergoing testing.”

“That person was tested negative in Japan but is being tested here because there are concerns about the sensitivity of the tests that were done in Japan,” Relucio clarified.

Napa County health officials say two coronavirus patients is the maximum the county can accommodate. Both patients will remain in quarantine at Queen of the Valley until all tests for the coronavirus come up negative.

Dr. Amy Herold, Chief Medical Officer at Queen of the Valley, said the hospital is working closely with the Centers for Disease Control and Prevention and Napa County Public Health to care for the two patients.

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“Out of caution, the patients are being monitored in special isolation rooms that have negative pressure to minimize the risk of exposure,” Herold said. “We are following established infection control protocols and working closely with our partners at CDC and Napa County Public Health to ensure the safety and well-being of our caregivers, patients and visitors.”