The Centers for Disease Control and Prevention (CDC) confirmed the nation’s first coronavirus case of unknown origin in Northern California, according to an article on The Sacramento Bee website. Since then at least two more such cases have been reported.
The infected individual had no known exposure to the virus through travel or close contact with a known infected person.
In such cases, public health officials trace the person’s contacts as they sleuth out where and how the person may have become infected and whether others have been exposed, the article said.
Earlier cases of person-to-person transmission in Illinois and in San Benito County came “after close, prolonged interaction with a family member who returned from Wuhan, China.
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