Health officials confirmed five new cases of coronavirus in California Monday, including two cases in Santa Clara County, bringing the county’s total cases up to nine.

San Mateo County, Sonoma County and Placer County also confirmed new cases of the respiratory illness, known officially as novel coronavirus or COVID-19.

Santa Clara County, which has the most cases of any California county, confirmed its eighth and ninth cases Monday, including a man who had contact with an infected person in another county, and a person who had household contact with another confirmed patient.

Both individuals are isolated at home, said Santa Clara County Public Health Department spokesperson Marianna Moles Monday. More information about the cases would not be released, Moles said.

In San Mateo County, meanwhile, one adult is hospitalized and awaiting confirmatory testing by the Centers for Disease Control and Prevention (CDC) after initial tests for the virus came back positive. The source of exposure to the virus is unknown; the person did not travel recently or have contact with a confirmed case.

San Mateo health officials are monitoring people with close contacts to that patient.

“This new case of a positive case of novel coronavirus has happened in San Mateo County and we share the concerns of the Centers for Disease Control and Prevention that we all need to be prepared for COVID-19 to spread within the United States,” said Dr. Scott Morrow, San Mateo County Health Officer in a brief statement, encouraging county residents to wash their hands and revisit emergency plans to stay at home for extended periods if necessary.

In Sonoma County, officials announced a presumptive-positive case in man who recently went on a cruise from San Francisco to Mexico, and has been in the county for ten days.

Placer County also confirmed their first case of coronavirus, in a worker at NorthBay VacaValley Hospital, the third employee to fall ill after being exposed to a Solano County woman with coronavirus who was hospitalized, but not tested for the virus until she was transferred to another facility. All three hospital employees are isolating themselves at home.

Nationwide, the death toll from coronavirus rose to six people Monday, after officials in Washington state announced the death of four more people. All the deaths from coronavirus in the U.S. have been in Washington.

The new cases in the Bay Area are not unexpected, according to public health officials, who for weeks have warned that more cases of the virus are likely, given the number of travelers from China and other countries to the region.

That was reflected in the number of Northern California cases confirmed this weekend. In addition to the two cases announced Monday, Santa Clara County confirmed five new cases between Friday and Sunday.

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California voters show little appetite for race-based affirmative action, lukewarm over “split-roll” property tax Alameda and Solano County are also dealing with two health workers from NorthBay VacaValley Hospital who fell ill.

The hospital workers were exposed to the Solano County patient for four days before she was transferred to UC Davis’s medical center when her condition worsened. At UC Davis, it took another four days before federal authorities tested her for coronavirus, and another three days before results were returned, prompting outrage among those concerned about community exposure to the virus.

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