Third dose COVID-19 'booster' shots available for patients with compromised immune systems

Immunocompromised patients can qualify for additional dose as FDA reportedly considers extra shots for all Americans


As COVID-19 cases rise due to the Delta variant, the Centers for Disease Control (CDC) has approved third dose vaccinations for patients whose immune systems are compromised moderately to severely. The CDC hopes the additional shot will boost immune protection for those who are at higher risk of complications from the coronavirus. 

UC Davis Health is now offering a third COVID-19 vaccine dose to patients whose immune systems are compromised
UC Davis Health is now offering a third COVID-19 vaccine dose to patients whose immune systems are compromised

UC Davis Health is reaching out to its patients who meet the CDC’s criteria for the third dose vaccinations to share the news. Appointments at various UC Davis clinics will begin later this week.  

The announcement comes as the Associated Press reports the FDA will soon consider approving additional doses for all Americans. According to the report, experts will recommend a third dose for people eight months after their second shot. For frontline health care workers who received their initial doses in December and January, that eight-month mark arrives in September. 

Currently, only those immunocompromised patients who received two doses of Pfizer or Moderna qualify for the protective third dose. Patients who received the Johnson & Johnson vaccine are not eligible at this time, per CDC guidance. 

Qualifying patients include those who:

  • Are receiving treatments for tumors or blood cancers
  • Are taking immunosuppressing medications, such as those taken after receiving an organ transplant
  • Are within two years of receiving CAR-T therapy or a stem cell transplant
  • Have primary immunodeficiencies, or rare genetic disorders that prevent the immune system from working properly
  • Have advanced or untreated HIV
  • Are taking high-dose corticosteroids (more than 20 milligrams of prednisone or its equivalent daily) or other drugs that may suppress immune response 

Certain chronic medical conditions may also qualify, such as chronic kidney disease or asplenia, which is living without a spleen. Some patients receiving dialysis may also need a third dose. 

The CDC recommends patients get the same manufacturer’s vaccine as their first two doses: Pfizer or Moderna. UC Davis Health plans to follow this guidance. However, the CDC notes switching between the brands is safe and allowed if necessary. According to the CDC’s recommendation for immunocompromised patients, the third dose must be given at least four weeks after the second dose.  

UC Davis Health patients who meet the criteria are being contacted to make appointments. In the coming weeks, third dose appointments will become available to immunocompromised people regardless of whether they are existing patients of UC Davis Health. Those appointments will be available at California’s

When to contact your provider

If you're experiencing COVID-19 symptoms, contact your primary care provider. UC Davis Health patients can use the MyUCDavisHealth symptom tracker. Telehealth video visits are also available during regular business hours.

If you have a medical emergency, call 911 and notify them of your COVID-19 symptoms.

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