COVID-19 Post-Vaccination Infection Data

The California Department of Public Health (CDPH) is identifying vaccination status of COVID-19 cases, hospitalizations, and deaths by analyzing the state immunization registry and registry of confirmed COVID-19 cases. Post-vaccination cases are individuals who have a positive SARS-Cov-2 molecular test (e.g. PCR) at least 14 days after they have completed their primary vaccination series or 14 days after they have completed their booster or additional dose.

Tracking cases of COVID-19 that occur after vaccination and/or boosters is important for monitoring the impact of immunization campaigns. While COVID-19 vaccines are safe and effective, some cases are still expected in persons who have been vaccinated, as no vaccine is 100% effective. For more information, please see https://www.cdph.ca.gov/Programs/CID/DCDC/Pages/COVID-19/Post-Vaccine-COVID19-Cases.aspx

Post-vaccination infection data is updated weekly and includes data on cases, hospitalizations, and deaths among the unvaccinated, those vaccinated with a primary series only, and those with an additional or booster dose. Partially vaccinated individuals are excluded. To account for reporting and processing delays, there is a 14 day lag in provided data (for example, for data through 1/23/2022, only data through 1/9/2022 will be made available). For deaths, there is an even greater lag in reporting, so more recent data should be used with caution. For display on the public dashboard, there is an additional 7-day lag for death data (21 days total). Note that this lag is separate from the difference in dates between data processing and updates to the website (in the above example, data through 1/9/2022 would be updated on the website on 2/2/2022).

Notes:

  • On February 2, 2022, the post-vaccination data has been changed to distinguish between vaccination with a primary series only versus vaccinated and boosted. The previous dataset has been uploaded as an archived table. Additionally, the lag on this data has been extended to 14 days.

  • On November 29, 2021, the denominator for calculating vaccine coverage has been changed from age 16+ to age 12+ to reflect new vaccine eligibility criteria. The previous dataset based on age 16+ denominators has been uploaded as an archived table.

Data and Resources

Field Value
accessLevel public
catalog_@context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
catalog_conformsTo https://project-open-data.cio.gov/v1.1/schema
catalog_describedBy https://project-open-data.cio.gov/v1.1/schema/catalog.json
identifier 55200999-06fa-43a1-816f-c11275b909e7
issued 2021-10-15T15:30:21.320742
modified 2022-07-29T13:00:16.016416
publisher California Department of Public Health
resource-type Dataset
source_datajson_identifier true
source_hash 6656030cf7964e8fea53ac600be4645811191a94
source_schema_version 1.1
theme {COVID-19,"Health and Human Services"}
Groups
  • AmeriGEOSS
  • National Provider
  • North America
Tags
  • amerigeo
  • amerigeoss
  • california-department-of-public-health
  • cases
  • ckan
  • covid
  • covid-19
  • covid19
  • geo
  • geoss
  • national
  • north-america
  • united-states
  • vaccines
isopen False
license_id notspecified
license_title License not specified
maintainer COVID-19 Response Data, Informatics, Surveillance, Clinical and Outbreaks (DISCO) Team
maintainer_email opendata@cdph.ca.gov
metadata_created 2025-11-20T17:44:02.952285
metadata_modified 2025-11-20T17:44:02.952289
notes The California Department of Public Health (CDPH) is identifying vaccination status of COVID-19 cases, hospitalizations, and deaths by analyzing the state immunization registry and registry of confirmed COVID-19 cases. Post-vaccination cases are individuals who have a positive SARS-Cov-2 molecular test (e.g. PCR) at least 14 days after they have completed their primary vaccination series or 14 days after they have completed their booster or additional dose. Tracking cases of COVID-19 that occur after vaccination and/or boosters is important for monitoring the impact of immunization campaigns. While COVID-19 vaccines are safe and effective, some cases are still expected in persons who have been vaccinated, as no vaccine is 100% effective. For more information, please see https://www.cdph.ca.gov/Programs/CID/DCDC/Pages/COVID-19/Post-Vaccine-COVID19-Cases.aspx Post-vaccination infection data is updated weekly and includes data on cases, hospitalizations, and deaths among the unvaccinated, those vaccinated with a primary series only, and those with an additional or booster dose. Partially vaccinated individuals are excluded. To account for reporting and processing delays, there is a 14 day lag in provided data (for example, for data through 1/23/2022, only data through 1/9/2022 will be made available). For deaths, there is an even greater lag in reporting, so more recent data should be used with caution. For display on the public dashboard, there is an additional 7-day lag for death data (21 days total). Note that this lag is separate from the difference in dates between data processing and updates to the website (in the above example, data through 1/9/2022 would be updated on the website on 2/2/2022). Notes: - On February 2, 2022, the post-vaccination data has been changed to distinguish between vaccination with a primary series only versus vaccinated and boosted. The previous dataset has been uploaded as an archived table. Additionally, the lag on this data has been extended to 14 days. - On November 29, 2021, the denominator for calculating vaccine coverage has been changed from age 16+ to age 12+ to reflect new vaccine eligibility criteria. The previous dataset based on age 16+ denominators has been uploaded as an archived table.
num_resources 4
num_tags 14
title COVID-19 Post-Vaccination Infection Data