A day after a Solano County resident tested positive for COVID-19, federal officials told the Fairfield-Suisun School Unified School District Thursday to prepare school sites for a potential outbreak of the pneumonia-like coronavirus.

In light of the directive from the U.S. Centers for Disease Control and Prevention, the district assured families in a message that staff has been working closely with Solano County Public Health officials for weeks to "ensure student and staff safety."

"While this may be alarming and cause fear, we want to assure you that FSUSD is taking precautions to keep our school sites disinfected and clean," the Fairfield-Suisun district said. "Our staff will wipe down commonly shared surfaces every day with disinfectants."

The Travis Unified School District, also in Solano County, and the Elk Grove Unified School District in Sacramento County said they received notices from the CDC to make similar preparations. District officials in Elk Grove said there are no confirmed cases in their district, according to KCRA.

“While this may be alarming to some parents, the risk to Solano County residents and the general public is still low at this time. We can assure you that our staff is doing everything in their power to keep school sites disinfected and clean for all students and staff,” the Travis Unified School District said in a statement posted on its website.

The Solano County patient was brought to UC Davis Medical Center from another Northern California hospital on Feb. 19, but it wasn't until four days later that the CDC heeded a request to test the patient for new coronavirus, according to an email sent to employees Wednesday by the hospital’s interim CEO Brad Simmons and David Lubarsky, CEO of UC Davis Health.

The patient arrived on a ventilator, and special protection orders were issued “because of an undiagnosed and suspected viral condition,” according to the email.

The hospital asked the Centers for Disease Control and Prevention to test for the coronavirus, but testing was delayed until Sunday “since the patient did not fit the existing CDC criteria for COVID-19,” the email said.

The CDC confirmed the test was positive on Feb. 26.

The hospital, which has treated other coronavirus patients, has been taking infection prevention precautions since the patient arrived. The email said officials believe that there was "minimal chance" others at the facility were exposed to the virus.

“Nevertheless, a small number of medical center employees have been asked to stay home and monitor their temperatures,” the email said.

An email sent to the CDC for comment was not immediately returned Wednesday night.

The CDC issued a statement on the new patient saying this is likely the first case of infection with unknown origin. "At this time, the patient’s exposure is unknown,'' the CDC said. "It’s possible this could be an instance of community spread of COVID-19, which would be the first time this has happened in the United States. Community spread means spread of an illness for which the source of infection is unknown. It’s also possible, however, that the patient may have been exposed to a returned traveler who was infected.''

The California Department of Public Health said it is tracing people who may have come in contact with the COVID-19 patient.

Amy Graff is a digital editor with SFGATE. Email her news tips at agraff@sfgate.com.

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