COVID-19-Outbreak-Data COVID-19 Outbreak Data

COVID-19 Outbreak Data

California law requires employers to report COVID-19 outbreaks to local health departments. Local health departments then report those data to CDPH. 

Non-healthcare employers are required to report to their local health department when they identify three or more cases of COVID-19 in a workplace within 14 days. Local health departments determine whether the cases constitute an outbreak, using CDPH outbreak definitions, and report confirmed outbreaks to CDPH.

Latest Outbreak Data

Update as of November 15

From January 1, 2021 to November 15, 2021, a total of 13,702 confirmed COVID-19 outbreaks and 147,933 outbreak-related cases were reported to CDPH. Of those outbreaks, 9,085 outbreaks (associated with 66,148 cases) began in 2021, and 4,617 outbreaks (associated with 81,785 cases) began in 2020.

Among outbreaks that began in 2021, the most common outbreak settings were:

  • Residential care facilities (19.2%)

  • Elementary and secondary schools (15.0%)

  • Skilled nursing facilities (9.8%)

  • Restaurants (5.2%)

  • Child day care services (3.9%)

  • Public safety, including police, fire, and correctional institutions (3.7%)

  • Community services, including homeless shelters (3.0%)

  • Construction (2.7%)

  • Hospitals (2.3%)

  • Grocery stores (2.0%)

Outbreak data does not equate to transmission risk within a particular industry. Because many settings have at times been either closed or open with capacity restrictions, numbers of outbreaks and cases in each setting do not directly reflect COVID-19 transmission risk in that setting. In addition, rates of outbreak identification and reporting may differ across settings, due to differences in testing and case tracking protocols. Also, the number of outbreaks in different settings will depend on the number of different workplaces in each setting. More outbreaks would be expected in settings with many workplaces compared to settings with few workplaces. 

While this report includes outbreaks reported between January 1, 2021 and November 15, 2021, some of these outbreaks reported during this timeframe began in 2020, as described above. Due to reporting delays, it is  also possible that additional outbreaks occurred during this time and have not yet been reported to CDPH.

For more information on reported outbreaks, visit the CHHS Open Data Portal. Data will be updated every two weeks.

More information for employers and local health departments about outbreak reporting: