The first case in the United States of an unknown origin was reported on Wednesday

Another patient in the United States has contracted the novel coronavirus (COVID-19) from an unknown origin, suggesting community transition in California.

The Washington Post reported that the latest patient to contract the from “community transmission” is a 65-year-old woman in Santa Clara County, California. The woman — who the outlet said was the second person-to-person case in the state — has not traveled to countries affected by the continued outbreak.

The news comes just two days after the first case of novel coronavirus in a patient who had not recently traveled abroad was reported in the U.S.

That case also occurred in California, the CDC said Wednesday, adding that the patient had not been exposed to anyone else known to be infected with the novel coronavirus.

On Friday, it was reported that the woman is in “serious condition,” as the source of her transmission remains a mystery.

Corona Virus
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Her case prompted the CDC to expand testing to anyone whom doctors suspect has the novel coronavirus, after she wasn’t tested for the virus for nearly a week after doctors expressed concerns that she had it.

Testing had previously been limited to people who had recently arrived back to the U.S. from China or had come into close contact of people who had already been diagnosed.

Dr. Nancy Messonnier, the director of the CDC’s National Center for Immunization and Respiratory Disease, spoke about this case in her press briefing Friday.

“It’s possible this could be the first instance of community spread — meaning the illness was acquired through an unknown exposure in the community. It’s also possible, however, that a thorough investigation may show that the patient had exposure through contact to a returned traveler who was infected,” she said.

Messonnier said that the CDC had sent a team to support California’s Department of Health and local health departments with the investigation into that case.

“We are working hard to find and identify how the patient was exposed as well as tracing back people who were exposed or might have been exposed to this patient,” Messonnier said.

Hong Kong Coronavirus
Workers from Department of Health in Hong Kong
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She later added, “While the immediate risk to the general American public remains low, and the U.S. government is doing everything we can to keep it low. CDC is constantly monitoring what is happening abroad.”

On Tuesday, Messonnier said in another briefing that it’s only a matter of time before the novel coronavirus arrives in the U.S. full force after other countries like Italy, South Korea and Iran saw spikes in the number of cases.

To prevent the spread of the virus, the CDC encourages maintaining basic forms of hygiene including careful hand washing, avoiding touching the face, moving away from people who are coughing or sneezing and staying home at signs of illness.