Important update: Healthcare facilities
CDC has updated select ways to operate healthcare systems effectively in response to COVID-19 vaccination. Learn more
To maximize protection from the Delta variant and prevent possibly spreading it to others, get vaccinated as soon as you can and wear a mask indoors in public if you are in an area of substantial or high transmission.
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.

How COVID-19 Vaccines Get to You

How COVID-19 Vaccines Get to You

Vaccine manufacturers; the federal government; state, local, and territorial jurisdictions; and other partners are working to make sure safe and effective vaccines are getting to you as quickly as possible. This page will help you understand the key steps in this important process and how CDC is tracking vaccine distribution, delivery, and administration throughout the United States.

Find a COVID-19 Vaccine: Search, text your zip code to 438829, or call 1-800-232-0233 to find locations near you.


Vaccine manufacturing

Vaccine manufacturing is complicated, and it can take months to make and package vaccines. Additionally, vaccines have to go through quality controlexternal icon testing during each and every step of their journey to make sure they are both safe and effective for use.


Vaccine allocation

Specific amounts of COVID-19 vaccine doses are made available (allocated) to jurisdictions* based on the number of people 18 years or older in the jurisdiction in proportion to the entire U.S. population. For the Pfizer-BioNTech and Moderna vaccines, which require receiving two doses to maximize immunity, allocations are split in two: 1) first-dose quantities that have already been released to the U.S. government and are under federal control at the time of allocation; and 2) additional doses that are still being manufactured and are not under federal control at the time of allocation. These doses are allocated but will be released at a future date so that communities can get second dose supplies.

After jurisdictions and other federal and commercial partners are allocated their supply, they determine where the vaccine goes, such as to:

* includes the 50 states; the District of Columbia; New York City, the U.S. territories of American Samoa, Guam, the Commonwealth of the Northern Mariana Islands, Puerto Rico, and the U.S Virgin Islands; and three independent countries in compacts of free association with the United States (Federated States of Micronesia, Republic of the Marshall Islands, and Republic of Palau).

vaccine truck

Vaccine ordering

Based on their allocation, jurisdictions and other federal and commercial partners order vaccines from the federal government using CDC’s vaccine ordering system, Vaccine Tracking System (VTrckS). Jurisdictions can order all or a portion of their weekly allocation. Any leftover doses are rolled over to the next week’s allocation.

vaccine truck
jurisdictional sites

Vaccine shipping

After vaccines are made, allocated, and ordered, they are shipped and delivered to vaccination providers such as health departments, hospitals, and pharmacies.

jurisdictional sites

Vaccine administration

After delivery, vaccine doses must then be given (administered) to the people who need them. The vaccine administration process requires strong cooperation and partnership among all the people working together at the federal, jurisdictional, and local levels to make sure people have access to and receive all recommended doses of vaccine. Health departments work with people in their jurisdictions to safely schedule appointments according to each jurisdiction’s vaccination plan. Health departments also work with providers and clinics to make sure they are ready to administer vaccines safely and efficiently. Retail pharmacies, long-term care facilities, and federal vaccination provider sites work with their staff and clients or patients to schedule vaccination appointments and administer doses.


CDC is tracking vaccine distribution and administration

CDC is using both new and existing information technology (IT) systems to collect reliable, rapid data about COVID-19 vaccines.

CDC reports COVID-19 vaccine doses delivered and doses administered in the United States publicly through the COVID Data Tracker: COVID-19 Vaccinations in the United States. CDC also reports data on COVID-19 vaccination in long-term care facilities. Because reporting data from multiple sources can cause duplicate entries that need to be checked and removed before CDC reports the data, data shown on CDC’s COVID Data Tracker data may not always match data reported by local jurisdictions.

CDC, other federal agencies, vaccination providers, state, local, and territorial public health departments, and tribal health facilities across the country use vaccine distribution and administration data to inform decisions about COVID-19 vaccination. COVID-19 Vaccination Reporting Overview provides an overarching view of the IT systems and how they integrate to track COVID-19 vaccine distribution and administration.

There are some factors that can cause delays in the vaccine journey and even delay the information submitted to the CDC COVID Data Tracker. These could include:

  • Technical issues delaying timely reporting
  • Vaccines needing to be redistributed within a jurisdiction, which could mean a longer time between initial distribution and administration
  • Jurisdictions having multiple data systems at the local and state levels
  • Providers not reporting vaccine administrations within the required 72-hour period

Much of the difference in the number of doses delivered and doses administered is expected. There always has to be sufficient supply available to clinics, pharmacies, and other vaccination provider sites to effectively run their vaccination programs, including making sure vaccine is available for people when they return for their second dose. CDC continues to work with jurisdictions and our other partners to ensure that vaccine is administered in the most efficient and effective way possible.