COVID-19 vaccines and IBD: What patients need to know
October 15, 2021

Should I get a COVID-19 vaccine if I have IBD?
Yes, you should get vaccinated against COVID-19, preferably with either the Pfizer-BioNTech or Moderna vaccines. All of the COVID-19 vaccines were rigorously tested for safety and effectiveness in clinical trials and do not contain any part of the actual virus. The Pfizer and Moderna vaccines each require two doses (shots) and rely on messenger RNA technology to teach our immune systems to recognize and defend against SARS-CoV-2, the virus that causes COVID-19. The other option is the one-dose Johnson & Johnson vaccine, which uses a harmless, genetically modified adenovirus to prime the immune system against SARS-CoV-2 (the adenovirus does not reproduce and is not related to the coronavirus that causes COVID-19). If you have any allergies to vaccine ingredients, you may not be eligible to take the vaccines — make sure to check with your doctor about this beforehand. The ingredients for the Pfizer-BioNTech vaccine, Moderna vaccine and Johnson & Johnson vaccine are listed online.
These vaccines continue to provide strong protection against severe illness and death from the virus that causes COVID-19 — including, importantly, the Delta variant. Most recently, the CDC has also stated that patients can get the COVID-19 vaccine at the same time as the vaccine for influenza.
Should IBD patients get an additional dose of vaccine or a booster?
The difference between an additional dose (a third dose if you received the two-dose vaccines; a second dose if you received the one-dose Johnson & Johnson vaccine) and a booster is important to understand.
The purpose of another dose is to provide additional stimulation for an appropriate immune response to the first dose(s) of vaccine. This was shown to be helpful for people who are on immunosuppressive treatments because of organ transplantation or who have received cancer chemotherapy. Patients with IBD are not in this category, and multiple studies have confirmed that their response to the vaccines is appropriate and that they do not need an additional dose.
The purpose of a booster is to boost a waning immune response. It’s possible we may all need a booster; consideration is being given to whether patients with IBD who are receiving specific therapies may need it. According to the CDC, people with IBD are eligible for a booster 28 days after their second dose of Pfizer or Moderna if they are:
- currently taking select therapies, including anti-TNF and anti-metabolites
- being treated with biologic agents that are immunosuppressive or immunomodulatory
- receiving high doses of steroids (more than 20mg of prednisone per day or the equivalent for more than two weeks)
Patients should ideally receive the same vaccine for their third dose.
We have reassured our patients that this is reasonable and safe, although there are still no data on whether patients with IBD have a higher rate of breakthrough infections or unfavorable outcomes from breakthrough infections. There are no data on patients with IBD losing response to their vaccines to the point of being essentially considered unvaccinated.
For now, there are no recommendations on additional doses for patients who received the Johnson & Johnson vaccine, and the CDC has not offered guidance on patients receiving targeted synthetic small molecules, such as tofacitinib and ozanimod.
Does the type of IBD therapy I’m receiving and timing matter when getting vaccinated?
It doesn’t matter whether you’re on maintenance therapy or actively inflamed and being treated to bring about remission: You do not have to time your vaccination to your medication cycle. All people with IBD should be vaccinated. An American College of Rheumatology task force examined the possibility of modifying the timing of therapy in patients receiving methotrexate or JAK inhibitors, but ultimately concluded that changing the timing — such as holding immune therapies around the timing of the vaccine — was not recommended. In other words, you should not delay getting vaccinated or stop your treatment. In clinical trials, the Pfizer-BioNTech, Moderna and Johnson & Johnson vaccines were all highly effective at preventing severe COVID-19.
Will COVID-19 vaccines cause my IBD to flare?
Recent research suggests the vaccines do not cause an increase in IBD flares. You may get a sore arm from the injection, and you may have side effects for a couple of days after being vaccinated, including fever, chills, fatigue and headaches. This is your immune system being trained to recognize and attack the virus. If those symptoms persist, contact your doctor.
If I've already had COVID-19, do I still need to get vaccinated?
It's important that you still get vaccinated, even if you've tested positive for COVID-19 in the past and recovered. Depending in part on how sick you were with COVID-19, your immune system may or may not have mounted a strong response and developed enough antibodies to protect you in the future. The vaccines are safe and effective; if you have some immunity to COVID from a prior infection, the vaccines will work even more effectively.
If I develop COVID-19, am I more likely to get really sick because of my IBD?
Some people have expressed concern that therapies for IBD may increase an individual’s chances of becoming severely ill from COVID-19. But multiple scientific studies have shown that’s not the case: Patients with IBD do not have a higher risk of getting infected with SARS-CoV-2 or developing COVID-19 and do not have a higher risk of becoming severely ill from it. Hospitalization and death rates for patients with IBD are the same as those in the general population; they’re even better for those receiving certain immune therapies (the hypothesis being these therapies reduce the hyperinflammatory phase of COVID-19).
How do patients with IBD respond to the vaccines?
Researchers have conducted several studies on how IBD patients’ immune systems respond to vaccination against COVID-19:
- The United Kingdom-based CLARITY-IBD study involving 2,052 patients receiving infliximab and 925 patients receiving vedolizumab found that patients receiving infliximab produced fewer antibodies after two doses of Pfizer-BioNTech or AstraZeneca at four months than patients receiving vedolizumab. It’s important to understand the study did not identify any difference in SARS-CoV-2 infection or COVID-19 between these groups, but these data have influenced the discussion on getting a booster dose.
- The U.S.-based PREVENT-COVID study found that IBD therapy did not significantly decrease antibody levels: 300 of 317 patients had detectable antibodies five months after receiving their two mRNA shots. Corticosteroids depressed antibody concentration, but they did not have a significant effect on vaccine ability to spark an immune response. Again, there are yet no data showing breakthrough infections or poor COVID-19 outcomes, but the antibody titer data support our recommendations and belief that the vaccines work well in people with IBD.
- The international ICARUS study revealed no significant difference in vaccine immune response after two doses of either Moderna or Pfizer-BioNTech between IBD patients and a control group, regardless of the therapy.
If you have questions about vaccine effectiveness in IBD patients, reach out to your doctor for more information.
COVID-19 Glossary
Antibodies: Proteins made by our immune system designed to recognize and attack other foreign proteins, such as those on the surface of viruses, bacteria or parasites.
Booster: A booster shot strengthens the immune memory in people whose immune response may have weakened over time.
COVID-19: Coronavirus disease 2019
Dose: A dose is part of the primary series of shots needed to produce an immune response against the virus.
SARS-CoV-2: Severe acute respiratory syndrome coronavirus #2, the coronavirus that causes COVID-19.
David T. Rubin, MD, is Chief of Gastroenterology, Hepatology and Nutrition and Co-Director of the Digestive Diseases Center.

David T. Rubin, MD
Dr. Rubin specializes in the treatment of digestive diseases. His expertise includes inflammatory bowel diseases (Crohn’s disease and ulcerative colitis) and high-risk cancer syndromes.
See Dr. Rubin's physician bio