Health workers to be quarantined in Solano County: Solano county public health officer Bela Matyas said at a news conference that the patient with no known source of infection visited to health centers before being diagnosed with coronavirus and health workers were exposed. Some of the workers are under isolation and some will be quarantined. Officials said the number is in the dozens — but under 100 people.

The first suspected U.S. case of a patient getting the new coronavirus through "community spread" — with no history of travel to affected areas or exposure to someone known to have the COVID-19 illness — was left undiagnosed for days because a request for testing wasn't initially granted, according to officials at UC Davis Medical Center in Sacramento, Calif.

The World Health Organization (WHO) named the coronavirus outbreak that originated in Wuhan, China, a public health emergency of international concern.

In the 1960s, doctors counting the number of chromosomes in human white blood cells noticed a strange phenomenon. Frequently—and more frequently with age—the cells would be missing the Y chromosome. Over time, it became clear this came with consequences. Studies have linked loss of the Y chromosome in blood to cancer, heart disease, and other disorders.