Vaccine efficacy rates vary among the immunocompromised


Ethan Kispert


Over the weekend, the Washington State Department of Health (DOH) recommended that immunocompromised patients receive a third dose of the COVID-19 vaccine. According to the department, health care providers across the state will start offering either the Moderna or the Pfizer vaccine to certain individuals following a review from the U.S. Food and Drug Administration (FDA). 


Stay one step ahead. Join our email list for the latest news.



The third dose for immunocompromised patients, however, is not to be considered a booster. Instead, the DOH says that the third dose is meant to be an additional dose for patients who haven’t developed immunities to an adequate level from the first two doses. 

During a “Covid-19 Vaccine Partner” call with the DOH, health officials stated that the COVID-19 vaccine efficacy (VE) for immunocompromised patients is at 59% to 72% versus 90% to 94% VE for non-immunocompromised patients.

State health experts also note that 40% to 44% of COVID-19 breakthrough cases involved immunocompromised patients who were fully vaccinated. 

Data from the DOH’s COVID-19 Data Dashboard shows that 71.5% of Washington residents over the age of 12 have received at least one dose of the COVID-19 vaccine.

The DOH’s recommendation comes after the White House issued a similar recommendation for third shots for immunocompromised individuals on August 12. 

During a press briefing, Dr. Rochelle Walensky, director of the CDC, touched on what the center has observed among immunocompromised patients. 

Dr. Walensky said:

“As we’ve been saying for weeks, emerging data show that certain people who are immunocompromised, such as people who have had organ transplant and some cancer patients, may not have had an adequate immune response to just two doses of the COVID vaccine.”

She noted that the percentage of patients with compromised immune systems makes up just 3% of the total adult population. 

Nonetheless, analysis by the CDC on sera from patients that have received either the Moderna or the Pfizer vaccine has found that there’s a wide variability in antibody responses towards various mutations of the coronavirus. With the two-dose Moderna and Pfizer vaccines, analysis from the same CDC report shows there’s a greater neutralization response by antibodies following the second dose versus the first dose. 

According to the CDC, the recommendation of a third shot for immunocompromised patients only applies to the Pfizer and Moderna vaccines, both of which are mRNA based. The center doesn’t have enough data on the J&J/Janssen vaccine yet to decide whether or not patients exhibit any benefit from a second shot. According to the report, the third shot should be 28 days after the second dose. 

The CDC sent out a recommendation on Wednesday that all people should receive a third dose of the COVID-19 vaccine. 

The statement said:

“Based on our latest assessment, the current protection against severe disease, hospitalization, and death could diminish in the months ahead, especially among those who are at higher risk or were vaccinated during the earlier phases of the vaccination rollout.”

Following the conclusion of an FDA review into the safety of a third dose of either the Pfizer or the Moderna vaccine, the CDC plans to begin vaccinating this fall. 

The statement said:

“We are prepared to offer booster shots for all Americans beginning the week of September 20 and starting 8 months after an individual’s second dose.”