Even After Vaccine, Immunocompromised Need to Stay Cautious

Since the beginning of the COVID-19 pandemic, healthcare experts have warned people who are immunocompromised to be extra cautious to avoid getting the virus, given their risk for severe complications. That’s because people who are immunocompromised have weakened immune systems that leave them more vulnerable to infection and illness, including COVID-19.

Given this elevated risk, those who are immunocompromised were among the first groups to be eligible for the COVID-19 vaccines. However, healthcare experts warn that immunocompromised people still need to be careful even if they’re fully vaccinated. In fact, the Centers for Disease Control and Prevention recommends that anyone who is immunocompromised continue to take COVID-19 safety precautions such as wearing a mask, practicing physical distancing and using good hand hygiene even after vaccination.

To learn more, we talked to Marcie Riches, MD, MS, director of the UNC Bone Marrow Transplant Program, and Pablo Serrano, MD, a UNC Health transplant surgeon.

Health Conditions and Organ Transplant Can Compromise the Immune System

When you’re immunocompromised, your immune system’s defenses are low, affecting its ability to fight off infections and diseases.

“Not only are (immunocompromised people) at greater risk for the normal infections we think about, like colds, they are at risk for more severe complications from those, as well as infections such as a mold infection in the lungs, which is not something you would usually have in a normal immune system,” Dr. Riches says.

Your immune system may be compromised for different reasons. These include:

  • Conditions such as HIV and AIDS that damage immune cells
  • Autoimmune diseases such as lupus and type 1 diabetes, which cause your immune cells to attack other parts of your body
  • Cancer treatments such as some types of chemotherapy that weaken your immune system as they destroy cancer cells
  • Organ or bone marrow transplants, which can compromise your white blood cells immediately after the transplant; post-transplant medications (anti-rejection drugs and immune suppressants) also can suppress your immune system

“Immunosuppression can come from a variety of scenarios, and probably those at greatest risk are patients who are receiving transplantation, which could be either solid organ transplant, like kidneys, liver or heart, or a bone marrow or blood stem cell transplant,” Dr. Riches says.

People Who Are Immunocompromised Need to Be Careful Even After Vaccination

Early research has shown that people who are immunocompromised because of a solid organ transplant do not appear to respond as well to the COVID-19 vaccines as the general population.

“They don’t form as many antibodies to the vaccine as other people,” Dr. Serrano says. “But they are still forming some and have a cellular response that can actually let them attack the virus and defend themselves from the virus, and they still have a lower risk of getting COVID-19. We still recommend they get vaccinated.”

In other words, the COVID-19 vaccines provide some protection, just not full protection, for those who are immunocompromised because of a solid organ transplant. It is still not known how well the COVID-19 vaccines protect others who are immunocompromised. UNC Health is part of a new national research study to determine how effective the vaccines are for those who have had a bone marrow or blood stem cell transplant.

“We have zero data on how well these vaccines are in the stem cell transplant population,” says Dr. Riches, who is co-leading the national study. “They are high risk for COVID, so we recommend the vaccine, but the caveat is we don’t know how effective it is.”

The study has started enrollment and will track 732 patients who have received a stem cell transplant for blood cancer in the past 12 months. They will receive a COVID-19 vaccine as part of their treatment plan. Findings from the study will provide physicians with the information they need to guide their recommendations about COVID-19 vaccines for these patients, such as the best time to receive a vaccination.

“We’re going to compare looking at early versus later vaccinations, so less than six months from transplant versus greater than six months, and the reason that we’re doing that is we think later vaccine is probably going to likely be more efficacious,” Dr. Riches says.

Until more is known, both Drs. Riches and Serrano recommend that people who are immunocompromised continue to follow safety precautions to avoid getting COVID-19 or any other illnesses.

“They still have to stay safe and stay protected. Avoid any place where there is a lot of people, and wear a mask,” Dr. Serrano says. “Follow the directions from their healthcare team.”


If you are immunocompromised, talk to your doctor about when to get your COVID-19 vaccine. Learn more here about participating in the research study that explores the effectivess of the COVID-19 vaccines in bone marrow or blood stem cell transplant patients.

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