IBD, Vaccines and Infection Risk

Immune-lowering medicines reduce the body's defence, so infections can be more frequent or more severe, and some dormant infections (such as tuberculosis or hepatitis B) can wake up. Live vaccines, which contain a weakened living germ, may cause infection in people with a weakened immune system and are generally avoided while on strong immune-lowering treatment. Vaccines made from inactivated (killed) germs or parts of germs are safe, though the response may be weaker on some medicines.

Infections are among the more common problems for people with IBD on immune-suppressing treatment, and many vaccine-preventable infections are avoidable. Despite this, vaccination is often missed, so asking about your vaccines at the start of treatment is worthwhile.

Before Umrah or Hajj, or other travel, speak with your IBD team early about required and recommended vaccines, as some travel vaccines are live and may not be suitable for you.

Before starting treatment, your team usually checks your vaccination history and tests for infections that could reactivate: hepatitis B (and often hepatitis C), tuberculosis (skin or blood test, chest X-ray when needed), and sometimes chickenpox immunity (varicella antibody) and HIV. When you are unwell, they test for infection with blood, stool, urine or chest tests.

Simple daily habits reduce infection risk.

• Wash hands often and avoid close contact with people who are clearly sick.

• Keep a record of your vaccines and bring it to appointments.

• Check with your IBD team before any travel vaccine, especially live vaccines.

• Stop smoking, take care of your skin and mouth, and have regular dental checks.

• Check household members' vaccines are up to date; some can protect you indirectly.

Food safety matters more when your immunity is lowered.

• Cook meat, poultry, eggs and fish thoroughly.

• Avoid unpasteurised milk and soft cheeses made from it.

• Wash fruit and vegetables and keep raw and cooked foods separate.

• Use safe drinking water, particularly when travelling.

Vaccines and protective medicines are part of IBD care.

• Inactivated vaccines (for example influenza each year, pneumococcal, hepatitis B, COVID-19, HPV, recombinant shingles) are considered safe on IBD treatment.

• Live vaccines (for example MMR, varicella, yellow fever) are usually avoided while on strong immune-lowering treatment; where needed, they are given in advance or after a planned break, only on your doctor's advice.

• If hepatitis B or latent tuberculosis is found, protective treatment may be started before or alongside your IBD medicine.

• Do not start antibiotics or stop IBD medicines on your own when you have a fever; call your team.

Your doctor decides which vaccines and timing suit your medicines.

There is no procedure for this topic. Testing is the main step.

• Screening blood tests and a TB test before starting biologic or similar treatment.

• Chest X-ray when tuberculosis screening is positive or unclear.

• Check antibody levels after some vaccines (for example hepatitis B) to confirm protection.

Guidelines from major IBD and gastroenterology societies recommend reviewing vaccines at diagnosis and giving inactivated vaccines (influenza, pneumococcal, COVID-19, hepatitis B, HPV and recombinant shingles vaccine as appropriate) as needed, ideally before starting strong immune-lowering therapy. Some people on certain medicines may need extra doses or antibody checks. Recommendations are updated regularly, so your doctor will confirm what applies to you.

With vaccination and sensible precautions, most people with IBD can safely stay on the treatment that keeps their disease controlled. Preventing infection helps prevent hospital stays and interruptions to treatment.

• Which vaccines do I need, and which should I avoid on my medicine?

• Should I be vaccinated before I start a new treatment?

• Have I been tested for hepatitis B and tuberculosis?

• What should I do if I get a fever while on treatment?

• Are my family's vaccines safe for me to be around?

This guide comes from the Saudi Gastroenterology Association (SGA) patient library, prepared by the Approved for publication by SGA; individual clinician review is ongoing. Last reviewed: 2026-04-24. It is for education and does not replace your doctor's advice.