New case of novel coronavirus identified in California, bringing state total to 7

Areas affected by the coronavirus (February 11, 2020) Areas affected by the coronavirus (February 11, 2020) Photo: Getty Images / Illustration Photo: Getty Images / Illustration Image 1 of / 32 Caption Close New case of novel coronavirus identified in California, bringing state total to 7 1 / 32 Back to Gallery

A new coronavirus case has been identified in San Diego, bringing the total number to seven in California and 13 in the United States.

This newly diagnosed unnamed female patient was found among more than 200 people who were evacuated from China to the Miramar military base in San Diego Wednesday. Her case is raising concerns about the reliability of assessments because she initially tested negative and was returned to quarantine with other healthy evacuees.

Originating in Wuhan, the new coronavirus has infected more than 42,000 people and killed more than 1,000 worldwide, according to the World Health Organization. The majority of cases are in China but the virus has spread to at least 25 other countries. Two deaths have been recorded outside mainland China, one in Hong Kong and one in the Philippines.

In California, both Santa Clara and San Benito counties have seen two cases each, and there is one each in Los Angeles and Orange counties. (See maps in gallery above to see where cases have been found in the U.S. and around the world.)

ALSO: Two coronavirus patients transferred to UC San Francisco

The San Diego patient and three other evacuees had been in hospital isolation in San Diego after showing symptoms of the virus. On Sunday, federal health officials said all four people had tested negative and were sent back to the base, joining more than 200 people under a 14-day quarantine.

On Monday morning, however, officials with the U.S. Centers for Disease Control and Prevention informed county health officials that “further testing revealed that one of the four patients tested positive" for novel coronavirus and the person was returned to hospital isolation, UC San Diego Health said in a statement.

Another evacuee from Miramar also was hospitalized for evaluation Monday afternoon, UC San Diego Health said in a statement.

“Both patients are doing well and have minimal symptoms," the statement said.

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Recent chartered flights have sent hundreds of Wuhan evacuees back to the U.S. They are being held in quarantine at military bases in California, Texas and Nebraska.

A plane carrying 178 American coronavirus evacuees from Wuhan landed early Wednesday at Travis Air Force Base, 50 miles northeast of San Francisco. All evacuees will be quarantined for 14 days and staying in isolation at the Westwind Inn on Travis AFB. They won't have any contact with people living and working on the base. Five of the evacuees taken to Travis Air Force Base were hospitalized after showing symptoms of the virus but none of those possible cases has been confirmed, authorities said.

Some 200 evacuees at March Reserve Air Base in Southern California were scheduled to be released from their two-week quarantine on Tuesday.

No symptoms were reported among evacuees at Lackland Air Force Base in San Antonio or a Nebraska national Guard training base in Omaha.

The Associated Press contributed to this story.

Amy Graff is a digital editor with SFGATE. Email her: agraff@sfgate.com.