In California , U.S.A , Marin County had less than 35 COVID-19 cases , Riverside County had less than 25 and San Luis Obispo recorded less than 15 cases by March 20 , 2020 .
Los Angeles County increased to 292 , Santa Clara County increased to 196 , San Mateo County increased to 100 , San Diego County increased to 97 , San Francisco County increased to 76 , Orange County increased to 65 , Sacramento County increased to 53 cases with 3 deaths , Contra Costa County increased to 46 , Alameda County increased to 45 , Marin County increased to 25 , Riverside County increased to 22 , San Joaquin County increased to 20 , Ventura County increased to 17 , Santa Cruz County increased to 15 , San Luis Obispo reported 13 cases , and Fresno County reported 6 cases including their first person-to-person transmission.
2020 coronavirus pandemic in California