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CONTRA COSTA CO., Calif. (KGO) -- Health officials announced on Tuesday that two novel coronavirus patients who were at Travis Air Force Base are now being treated at hospitals in Contra Costa County.They were transported early Tuesday morning from the air force base, which is where some international travelers were being quarantined because they may have been exposed to the virus.The patients were among recent U.S. evacuees from the Diamond Princess cruise ship in Japan, officials say. They're being cared for in Contra Costa County due to lack of space at facilities closer to the base. Officials say they were not infected with the virus in the county.Health officials say that while the patients have tested positive for the virus, they have yet to show any symptoms."Our county's healthcare system is prepared to handle COVID-19," said Dr. Chris Farnitano, Contra Costa County Health Officer. "We have been working with our hospital partners to follow safety protocols to keep patients and healthcare workers safe and minimize the risk of the virus spreading in Contra Costa," said Dr. Chris Farnitano, Contra Costa County Health Officer.