What We Know About COVID-19 Vaccines for People Who Are Immunocompromised

Public health officials have warned that people who are immunocompromised need to be especially cautious when it comes down to preventing COVID-19 infection. Even though COVID-19 vaccines have been made available to all Americans over the age of 5 as of March 2022, there are still warnings for immunocompromised people to be careful—even if they're fully vaccinated.

If you're not immunocompromised or don't have a close friend or family member with a weakened immune system, you probably haven't given this much thought. But if you or someone you know does fall into the immunocompromised population, it's understandable to have questions. Here's what you need to know.

What Does It Mean To Be Immunocompromised?

People who are immunocompromised have a weakened immune system, according to the National Cancer Institute (NCI). That means they aren't able to fight infections and other diseases as well as others who aren't immunocompromised.

There are several health conditions and diseases that can cause a person to be immunocompromised, including "AIDS, cancer, diabetes, malnutrition, and certain genetic disorders," wrote the NCI. Some medications and treatments like anticancer drugs or organ transplants, respectively, can also make a person immunosuppressed.

Why Might People Who Are Immunocompromised Not Have Full Protection With the COVID-19 Vaccine?

"In general, people who are immunocompromised may not respond to vaccines as well as those who aren't immunocompromised," John Sellick, Jr., DO, an infectious disease expert and professor of medicine at the University at Buffalo/SUNY, told Health. "We knew this was going to be a problem with the COVID-19 vaccine all along," added Dr. Sellick.

Research has also found that SARS-CoV-2, the virus that causes COVID-19, can cause more severe illness in people who are immunocompromised and even survive longer in their bodies because of the way their immune system responds.

"In some instances, it is possible that patients who are immunocompromised might not generate as robust an immune response," Prathit Kulkarni, MD, assistant professor of medicine in infectious diseases at Baylor College of Medicine, told Health. Dr. Kulkarni said, as a result, "they may remain susceptible" to contracting COVID-19, even if they've been fully vaccinated.

The experience is not the same for each person in the immunocompromised population either. "The state of being immunocompromised is quite variable," explained Dr. Kulkarni. "Some forms of immunocompromise, such as chemotherapy for leukemia or medications that need to be taken after organ transplantation, can be quite significant. There is a range of what constitutes the immunocompromised state, and different situations might pose a different risk."

There's also this to consider: People who are immunocompromised weren't included in the original clinical trials for the COVID-19 vaccines. "For practical reasons during the middle of the pandemic, it was needed to proceed quickly to determine the safety and efficacy of the COVID vaccines," said Dr. Kulkarni. "This did create a gap in our understanding of the immune response to vaccine in this particular group of patients."

What Should You Do About the COVID-19 Vaccine if You're Immunocompromised?

Experts said it's still important to get vaccinated. "Currently, immunocompromised patients are recommended to receive any of the standard COVID vaccines," said Dr. Kulkarni. As of April 2022, the CDC has provided vaccination guidance for individuals who are considered to be moderately or severely immunocompromised.

The vaccine is especially important for people who are immunocompromised because they "could be at higher risk for a worse outcome from COVID-19 depending upon their particular type of immunocompromised state," added Dr. Kulkarni. Dr. Kulkarni further noted that this is the reason why mask use and physical distancing are still important if you have a weakened immune system—even if you are fully vaccinated.

As research continues, there might be different or improved vaccine alternatives for getting these individuals as much protection from COVID-19 as possible, like increasing antibody counts. "We…have high-dose vaccines for influenza that give you more antibodies—a higher dose could be a possibility for COVID-19," said Dr. Sellick.

Measures could also call for a change in the number of vaccine doses immunocompromised individuals are given. A March 2022 meta-analysis published in the BMJ seemed to support this option. Researchers explored how effective COVID-19 vaccines were for individuals considered to be immunocompromised. Across 82 studies, the researchers came to the conclusion that second doses and booster doses would be beneficial for immunocompromised individuals.

Additionally, situations may arise where someone who is immunocompromised may not be able to take the vaccine because of severe COVID-19 vaccine allergic reactions or due to a low level of immune system response. As of May 2022, the CDC has indicated Evusheld, an investigational medicine with two antibodies formulated to help prevent COVID-19, as another method of protection for eligible individuals in this population.

In any case, if you or someone close to you falls into the immunocompromised population, you can always talk to your healthcare provider about the best course of action for your situation to stay protected from COVID-19.

The information in this story is accurate as of press time. However, as the situation surrounding COVID-19 continues to evolve, it's possible that some data have changed since publication. While Health is trying to keep our stories as up-to-date as possible, we also encourage readers to stay informed on news and recommendations for their own communities by using the CDC, WHO, and their local public health department as resources.