County of Marin - News Releases - COVID-19 Third Dose Clinic

For Immediate Release
August 19, 2021

Vaccine Clinic Planned for 3rd Dose-Eligible People

Mass Vaccination Day Targets Severely Immunocompromised Marin Residents

San Rafael, CA – Marin County Public Health is ensuring all Marin residents who are severely immunocompromised have access to the recently approved third dose of COVID-19 vaccine by offering a special clinic exclusively for eligible Marin County residents. This is especially helpful to patients of healthcare providers who may not have the ability to provide COVID-19 vaccines in-house or match the increase in demand among immunocompromised patients.

The one-day mass vaccination event will take place Saturday, August 21 at the Marin Center (site of the Marin County Fairgrounds). The event is made possible by a partnership with Safeway.

Third doses are available for moderately to severely immunocompromised people who have completed a Pfizer or Moderna vaccination series more than 28 days ago and have:

  • Been receiving active cancer treatment,
  • Received an organ or stem cell transplant and are taking medicine to suppress the immune system,
  • HIV infection, or
  • Active treatment with high-dose corticosteroids or other drugs that suppress the immune system.

Appointments are encouraged, and vaccine seekers should bring an ID, their COVID-19 vaccination card, health insurance or medical coverage card (if they have one) and be prepared to attest that they are eligible for the third dose. Documentation from a healthcare provider is not required. The additional dose will be matched to the initial vaccination type. At this time, FDA authorization does not extend to those who received the Johnson & Johnson vaccine.

The U.S. Centers for Disease Control and Prevention (CDC) estimates that about 2.7% of the population of the United States is immunocompromised, including organ transplant recipients, people undergoing cancer treatment, and those with other immunodeficiencies. In Marin, approximately 10,000 residents meet that criterion. This population is more likely to become infected with COVID-19, even after vaccination, compared with similarly vaccinated but otherwise healthy individuals. They are also more likely to become severely ill due to COVID-19. 

“A third dose helps boost the protection for people with severely weakened immune systems,” said Dr. Matt Willis, Marin County Public Health Officer. “It’s also important to remember that those of us who are fully vaccinated and have normal immune response are well protected, and don’t need an additional dose yet.”

People should talk to their healthcare provider about their medical condition, and whether getting an additional dose is appropriate for them. Third doses for the general public is still under review by the CDC and U.S. Food and Drug Administration (FDA). Depending on the FDA’s decision, third doses could be available for a wider range of people beginning in mid-September.

If a Marin County resident is eligible but cannot attend the August 21 mass vaccination event, they are encouraged to seek a vaccine from their medical provider or find a vaccine provider near them. Currently, Marin-based vaccine providers offering third doses include:

In addition, Marin County Public Health is offering third doses at its mobile vaccination clinics, as supply allows.  Advance appointments are required. For more information about COVID-19 vaccines and to find a Marin County Public Health vaccine clinic near you, visit


Laine Hendricks
Public Information Officer
County Administrator's Office

3501 Civic Center Drive
Suite #325
San Rafael, CA 94903
(415) 473-7496
Email: Laine Hendricks
County Administrator website