Patient who wasn't immediately tested could be first coronavirus case without clear source

Bita Ryan and Phil Helsel

The head of a Sacramento health system says that the Centers for Disease Control and Prevention did not immediately test a patient infected with the coronavirus, in what may be the first case of community spread in the U.S.

Dr. David Lubarsky, the CEO of University of California, Davis, Health, said in a note to staff obtained by NBC News that after the patient was transferred to UC Davis Medical Center on Feb. 19, it asked the centers to conduct testing but the federal agency declined.

"We requested COVID-19 testing by the CDC, since neither Sacramento County nor CDPH is doing testing for coronavirus at this time," said the note, which was signed by Lubarsky and UC Davis Medical Center interim CEO Brad Simmons. (CDPH is an acronym for California’s Department of Public Health.)

"Since the patient did not fit the existing CDC criteria for COVID-19, a test was not immediately administered. UC Davis Health does not control the testing process," the two officials wrote in the letter.

On Sunday, the CDC reversed its decision and ordered the test, and on Wednesday, the federal agency confirmed that the patient had tested positive, Lubarsky and Simmons wrote.

The CDC did not immediately respond to a request for comment late Wednesday.

Lubarsky and Simmons wrote that from the time the patient was transferred to UC Davis Medical Center, precautions were taken to prevent exposure because it suspected a viral infection.

"This is not the first COVID-19 patient we have treated, and because of the precautions we have had in place since this patient's arrival, we believe there has been minimal potential for exposure here at UC Davis Medical Center," the memo said. It was later posted to the UC Davis Health website.

Full coverage of the coronavirus outbreak

The case is being investigated, but it could be the first case of person-to-person transmission of the illness caused by the new coronavirus in the general public in the United States.

The patient had no known exposure to the virus through travel or close contact with a known infected individual, California's health department said.

There have been at least two other person-to-person transmission cases in the U.S., but both involved spouses of people who had traveled to China. A husband in Chicago whose wife traveled to the Chinese city of Wuhan tested positive, and that couple was released from a hospital earlier this month.

The other involved a husband and wife in San Benito County in Northern California, and the husband had recently traveled to the Wuhan but his wife had not, authorities have said.

The coronavirus outbreak has spread from China to at least 40 countries around the world, affecting markets and disrupting travel. A recent increase in cases in Italy, Iran and South Korea have heightened concerns about the ability to contain the spread of the virus.

Cases in the U.S. have been limited, though the Centers for Disease Control and Prevention said that Americans should prepare for the spread of the coronavirus in communities.

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