Will You Need To Get A Fourth COVID-19 Vaccine Shot?

According to the U.S. Centers for Disease Control and Prevention (CDC), some immunocompromised people in the U.S. may need to get a fourth shot of the mRNA COVID-19 vaccines. While the CDC didn't make an official recommendation, the agency updated its COVID-19 vaccine guidelines on Tuesday, October 25 to indicate that people who are moderately or severely immunocompromised or have certain underlying medical conditions may require additional protection against the virus. The new guidance doesn't apply to people with healthy immune systems. 

This update comes just 2 months after the CDC approved booster shots, or third doses, of the mRNA vaccines for adults with weakened immune systems. Much like the third booster shot, immunocompromised adults can get a fourth dose of either the Moderna or Pfizer-BioNTech vaccines approximately 6 months after receiving their third dose (via Axios). The CDC says the additional dose may be necessary for people with underlying conditions who didn't have a robust immune response after receiving the first 2 doses of the mRNA vaccines.

Who is eligible for a fourth shot?

According to a study from Johns Hopkins University, fully vaccinated people with compromised immune systems are 485 times more likely than most vaccinated people to be hospitalized with COVID-19 or die from the virus (via CNN). Other smaller studies also show that vaccinated immunocompromised people account for 44% of all breakthrough COVID-19 cases that lead to hospitalization. Fortunately, booster shots have been proven to increase the antibody response in many immunocompromised adults — so who exactly is eligible for a fourth shot of the vaccine?

According to the CDC, people with certain conditions, like cancer and advanced or untreated human immunodeficiency virus (HIV), organ transplant and stem cell recipients, and people who take immunosuppressants are all eligible for a fourth dose. Nearly 9 million people, or 2% of the U.S. population, fit into this criteria. Since this new guidance isn't an official recommendation, however, anyone who falls into this category should consult with their doctors before getting a fourth booster shot to discuss whether or not an additional dose is actually necessary.