Vaccines when your immune system is compromised

Vaccines help stimulate your immune system to fight off certain diseases. A compromised immune system can't recognize and fight off bacteria, viruses or other germs the way a healthy immune system can.

That means you may need to take extra precautions. Among the most important is getting the vaccines you need at the appropriate times. Know which vaccines pose a threat and which can help protect you.

Beware of live vaccines

Vaccines can partially compensate for an impaired immune system. Which vaccines are recommended if you have a weakened immune system depends on your particular condition.

Most vaccines contain weakened or killed microbes — such as viruses or bacteria — or just parts of microbes. Other vaccines use inactivated toxins produced by microbes. Your doctor may avoid giving you live viral vaccines, such as measles-mumps-rubella (MMR) or chickenpox (varicella) vaccines, because the live viruses may cause complications if you're immunocompromised.

Protection not absolute, but still valuable

Vaccinations can't completely protect someone with an impaired immune system. For example, when the average healthy person receives the influenza vaccine, the vaccine is about 70 percent to 90 percent effective in preventing influenza. In older adults who are immunocompromised, the vaccine might be only 30 percent to 40 percent effective. But your doctor may recommend vaccination anyway because some protection is better than none.

What to do if you can't get vaccinated

If your illness or condition prevents you from getting all the vaccinations you'd otherwise want, you can still protect yourself. For starters, be sure to get enough sleep, eat nutritious foods and stay physically active.

You can further protect your health with these tips:

• Avoid crowds or wear a mask to prevent respiratory infection.
• Wash your hands frequently and thoroughly with soap and water, or use an alcohol-based hand sanitizer.
• Avoid putting your fingers into your mouth or eyes.
• Ask close contacts, for instance, family members or caregivers, to be vaccinated for influenza, MMR and chickenpox if they aren't already immune.
• Contact your doctor promptly if you develop a fever or any unusual symptoms that might indicate an infection.
• Check on additional vaccines if you plan to travel to another country.
• Wear a medical alert bracelet or carry a wallet card stating that you're immunocompromised.

Taking advantage of available vaccines and implementing other preventive measures add a secondary line of defense against infectious disease — and can be lifesaving if you're living with a weakened immune system.