A woman in the Bay Area who became ill after returning from a trip to China has become the ninth person in the U.S. to test positive for a new virus, health authorities said Sunday.

Within hours, two more cases of the virus were confirmed in San Benito County, just south of Gilroy, bringing the national total to 11.

Confirmed Coronavirus Cases

The first and second cases of the novel coronavirus in Santa Clara County were confirmed in the past three days, but the two cases are not related, according to the county Public Health Department.

The San Benito County cases are a husband and wife, both 57, health officials said. The husband recently traveled to Wuhan, China, the epicenter of the coronavirus. The wife did not join him, so the transmission has been person-to-person, but officials confirmed that neither of the patients have left the home since the husband's return from China. San Benito County Public Health Services said that all recommended guidelines are being followed.

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The San Francisco case, a visitor to the U.S., had recently traveled to Wuhan. She arrived Jan. 23 to visit family, officials said in a news release.

The patient has stayed at home with family since she arrived, except for two occasions when she sought outpatient medical care. She has been regularly monitored and was never sick enough to be hospitalized, the release said.

The woman's family members have also been isolated at the home. The health department has been bringing them food and other necessities, officials said.

"A second case is not unexpected. With our large population and the amount of travel to China for both personal and business reasons, we will likely see more cases, including close contacts to our cases," Dr. Sara Cody, the county's health officer, said in a statement.

The first case in the Bay Area was a man who traveled to Wuhan and Shanghai before returning Jan. 24 to California, where he became ill, Cody said Friday.

The man was also never sick enough to be hospitalized and "self-isolated" by staying home, she said.

The man left home twice to seek outpatient care at a local clinic and a hospital. Public health officials are now trying to reach anyone he may have come into contact with during those times to assess whether they were exposed to the virus.

Three new cases of the coronavirus were confirmed in California on Sunday. One was in the Bay Area and two were in San Benito County, south of Gilroy. Marianne Favro reports.

Those people, along with the few members of his household, will have to undergo a 14-day quarantine.

The San Francisco Department of Public Health said Monday two of the area coronavirus patients arrived at a San Francisco hospital Monday morning for treatment, adding that there was no elevated risk to the public. To protect the patients' privacy, the DPH did not name the hospital or provide more patient information.

Health officials believe it can take up to two weeks for someone who is infected to get sick.

The virus has infected almost 10,000 people worldwide and killed more than 200. The vast majority of the cases and all but one of the deaths have been in China. The first death outside China from the new virus was recorded Sunday in the Philippines.

Cody said there was no risk of infection for the general public from the Santa Clara County cases.

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Nearly 200 Americans who were evacuated from Wuhan are under a 14-day quarantine at a military base outside Los Angeles — the first by the government in half a century.

Other cases of the new pneumonia-like virus include two in Southern California, one in Massachusetts, one in Washington state, one in Arizona and two in Chicago.