COVID-19: County of San Mateo Data as of 3/31/2020

  • Due to the current testing capacity, the number of cases detected through testing represents only a small portion of the total number of likely cases in the County. This means the number of cases by age group is skewed toward those who are high risk and tested.
  • COVID-19 data are reported as timely, accurately, and completely as we have available. Data are updated as we receive information that is more complete and will change over time as we learn more. Data reported as of 3/31.
  • Cases are lab-confirmed COVID-19 cases reported to San Mateo County Public Health by providers, commercial laboratories, and results reported through the California Reportable Disease Information Exchange (CalREDIE).

For more information and up to date news on COVID-19 in San Mateo County, visit