Important update: Healthcare facilities
CDC has updated select ways to operate healthcare systems effectively in response to COVID-19 vaccination. Learn more
Given new evidence on the B.1.617.2 (Delta) variant, CDC has updated the guidance for fully vaccinated people. CDC recommends universal indoor masking for all teachers, staff, students, and visitors to K-12 schools, regardless of vaccination status. Children should return to full-time in-person learning in the fall with layered prevention strategies in place.
The White House announced that vaccines will be required for international travelers coming into the United States, with an effective date of November 8, 2021. For purposes of entry into the United States, vaccines accepted will include FDA approved or authorized and WHO Emergency Use Listing vaccines. More information is available here.
Travel requirements to enter the United States are changing, starting November 8, 2021. More information is available here.

COVID-19 Vaccination Data Systems and Data Sources

COVID-19 Vaccination Data Systems and Data Sources

CDC reports COVID-19 vaccination data online on COVID Data Tracker and in vaccination datasets. Sharing timely and accurate information with the public is one of CDC’s core activities. Timely and accurate reporting from jurisdictions provides the reliable data that can be reported by CDC. All reported numbers may change over time as updated data are continuously reported to CDC.


CDC uses multiple information technology systems to rapidly collect reliable data about how many doses of COVID-19 vaccines have been distributed and how many people have been vaccinated with those doses (administration). CDC — together with other federal agencies, vaccine providers, jurisdictions, state/local public health departments, and tribal health facilities across the United States — uses these data systems to inform decision-making regarding COVID-19 vaccination. The COVID-19 Vaccination IT Overview provides an overarching view of the vaccine IT data systems and how they integrate to track COVID-19 vaccine distribution and administration.

Vaccine Distribution Data Systems

  • Vaccine Tracking System (VTrckS) is CDC’s vaccine order management system where jurisdictions (states, territories, tribes, and local entities), federal agencies, and pharmacy partners order vaccines from the federal government.
  • VTrckS Provider Order Portal (VPOP)external icon is CDC’s platform where federal entity providers report their on-hand COVID-19 vaccine inventory each day.
  • Immunization Data Lake (IZ Data Lake) is a cloud-hosted data repository to receive, store, manage, and analyze deidentified COVID-19 vaccination data.

Vaccine Administration Data Systems

  • Immunization Information Systems (IISs)Most IISs create a centralized data repository for storing vaccination information specific to that jurisdiction.
  • Vaccine Administration Management System (VAMS) is a web-based application available to support planning and execution for temporary, mobile, or satellite COVID-19 vaccination clinics. VAMS connects with IISs and sends data to IISs through the COVID-19 Data Clearing House.
  • COVID-19 Data Clearing House is a cloud-hosted data repository that receives, deduplicates, and deidentifies COVID-19 vaccination data, which are then used to populate the Immunization (IZ) Data Lake.
  • Immunization Data Lake (IZ Data Lake) is a cloud-hosted data repository to receive, store, manage, and analyze deidentified COVID-19 vaccination data.

COVID-19 Vaccination Data Sources

Federal Agency Data

  • On CDC COVID Data Tracker (CDT), data are individually displayed at the national level and included as part of national totals for each metric for the following agencies (except Department of State, DoS):
    • Bureau of Prisons (BoP)
    • Department of Defense (DoD)
    • Indian Health Services (IHS)
    • Veterans Health Administration (VHA)
  • Federal agency data are also included as part of jurisdiction, state, or territory aggregate metrics. To avoid duplicate counts, the agency data should not be combined with other data.
  • When denominator data are available for a federal agency, metrics such as rate per 100,000 and percent of the population are calculated. When the denominator data are not available for federal entities, these metrics are displayed as “N/A” or entered as “0.”

Jurisdictions and Other Reporting Partners

National and jurisdictional metrics reported on CDT include vaccination data distribution to and administered in the following locations:

  • Jurisdiction (state, territory, tribe, or local entity) partner clinics
  • Retail pharmacies
  • Federal partners and programs such as
    • Federal Pharmacy Partnership for Long-term Care (LTC) Program
    • Dialysis centers participating in the Federal Dialysis Center Program
    • Federal Emergency Management Agency (FEMA)
    • Health Resources and Services Administration (HRSA)

Population Data Sources


CDC calculates rate and percentage measures for vaccination among the entire population and among select demographic groups (such as people ages 65 years or older).

CDC/ATSDR & Surgo Ventures

Social Vulnerability Index (SVI) scores, which range from 0 to 1, are from CDC/ATSDR’s Geospatial Research, Analysis, and Service Program. COVID-19 Community Vulnerability Index (CCVI) scores, which also range from 0 to 1, are from Surgo Ventures.

COVID-19 Community Vulnerability Index (CCVI) scores, which also range from 0 to 1, are from Surgo Venturesexternal icon.

National Immunization Survey

Race/ethnicity is not available for some of the records that are directly reported to CDC. Thus, data reported to CDC significantly underestimate the race/ethnicity percentages and are not generalizable to the entire population of individuals with COVID-19 vaccination. CDC is providing information on self-reported COVID-19 vaccination status by race/ethnicity from the National Immunization Survey (NIS) Adult COVID Module to supplement vaccine administration data reported directly to CDC by jurisdictions and federal entities.

Reporting Conditions

Jurisdictions currently collect demographic data and report it to CDC. Not all states and territories report to CDC demographic data on vaccine recipients; the laws in each state or territory dictate whether the state can collect or report demographic data.

Jurisdictional Reporting Conditions

Texas has historically provided COVID-19 vaccination administration data to CDC in aggregate format, which impacted CDC’s ability to report metrics requiring information at the individual dose level. Although Texas still reports vaccination data in aggregate form, Texas and CDC recently collaborated to update the format of this record submission to improve COVID-19 reporting of Texas’ data on CDC’s COVID Data Tracker at the national, state, and county levels.

Previously, for Texas, CDC estimated the number of people with at least one dose and the number of people who are fully vaccinated for the populations ages 12 years or older, 18 years or older, and 65 years or older in the metrics for Texas alone and when including Texas in the national level metrics on the Vaccinations in the United States site. Additionally, Texas was omitted from several demographic and county-level graphics pages. Further, prior to October 22, 2021, all records reported by Texas were assumed to be for residents of Texas.

  • Beginning September 28, 2021, age-based metrics for Texas are directly reported rather than estimated for the populations ages 12 years or older, 18 years or older, and 65 years or older on the Vaccinations in the United States site.
  • Beginning September 28, 2021, the national counts for booster dose data on the Vaccinations in the United States site include Texas.
  • Beginning October 22, 2021, county-level graphics on Vaccinations by County, Vaccination Equity, and Vaccinations and Other Outcomes include Texas.
  • Beginning October 22, 2021, CDC is able to attribute non-residents of Texas to their respective state or territory of residence. Texas residents who received a COVID-19 vaccination in a different state or territory are also now attributed to Texas’ population-based metrics.
  • Beginning November 18, the Vaccination Demographics and Demographic Trends sites include vaccination demographic information from Texas.

New Hampshire lifted its national COVID-19 emergency response declaration in May 2021, which allows vaccine recipients to opt out of having their COVID-19 vaccinations included in the state’s IIS. As such, data submitted by New Hampshire since May 2021 may not be representative of all COVID-19 vaccinations occurring in the state.

County-level Reporting

  • California does not report the county of residence for persons receiving a COVID-19 vaccine when the resident’s county has a population of fewer than 20,000 people.
  • Hawaii does not provide county-of-residence information when reporting COVID-19 vaccination data to CDC.
  • Massachusetts does not provide COVID-19 vaccination data for Barnstable, Dukes, and Nantucket counties because of their small populations.