Travelers with Weakened Immune Systems

Many illnesses can weaken the immune system, including HIV/AIDS, different kinds of cancer, liver disease, kidney disease, and multiple sclerosis. In addition, many medicines can weaken the immune system, including steroids, cancer chemotherapy, and drugs to treat rheumatoid arthritis or psoriasis. Regardless of the cause, if you have a weakened immune system and are planning a trip overseas, make an appointment with a travel medicine specialist to talk about what you should do to prepare for safe and healthy travel.

Vaccines

Check the CDC Travelers’ Health website to see what vaccines might be recommended for your destination, and talk to your doctor about which of them are right for you. Most travel vaccines are made from killed bacteria or viruses and can be given safely to people with weakened immune systems. However, they may be less effective than in people with normal immune systems, and you may not be fully protected. Your doctor may recommend blood tests to confirm that a vaccine was effective, or he or she may recommend additional precautions to keep you safe.

Some vaccines, such as MMR (measles, mumps, and rubella) and varicella, are made from live viruses. Many people with weakened immune systems should not receive these vaccines. Talk to your doctor what your options are for protecting yourself against these diseases.

Yellow fever vaccine is made from a live virus, and it cannot be safely given to people whose immune systems are very weak, such as people with HIV infection and low T-cell counts or people receiving cancer chemotherapy. If there is a risk of yellow fever at your destination, CDC recommends delaying your trip until your immune system is strong enough for you to have the vaccine. Some countries may require the vaccine, even if there is no risk of yellow fever. If that’s the case, ask your doctor about a medical waiver for the vaccine.

Medicines

If there is a risk of malaria at your destination, you may need to take medicine to prevent it. People who have weakened immune systems can get seriously ill from malaria, so it’s important to closely follow your doctor’s instructions for taking the medicine, which may include taking it for several weeks before and after the trip. You should also take steps to avoid mosquito bites: wear insect repellent, wear long pants and sleeves, and sleep under a net if your rooms are exposed to the outdoors.

Depending on where you are going and your planned activities, your doctor may also prescribe medicine to prevent altitude illness or to treat travelers’ diarrhea. These drugs, as well as any you are prescribed to prevent malaria, can interact with medicines you usually take. Make sure your travel doctor knows about all the medicines you take regularly, including vitamin supplements, so that he or she can anticipate potential interactions.

Other Precautions

Not all illnesses can be prevented with vaccines or medicines, and people with weakened immune systems are especially prone to travelers’ diarrhea. Make sure you follow CDC’s advice for eating and drinking safely. You should also wash your hands often and try to avoid touching surfaces that other people have touched, such as doorknobs and stair rails, with your bare hands.

With a little advance preparation and a few precautions, people who have weakened immune systems can safely travel almost anywhere in the world.