Understanding the risks and benefits
Since the 1950s, vaccines have been used to ward off many childhood illnesses, including polio, measles and mumps. The immune system, a complex network of organs, tissues, cells and proteins, normally responds to vaccines by fighting off the weakened or killed form of the germ used to make the vaccine. Immunity is the end result.
In some children with a primary immune (PI) deficiency, however, their immune systems are unable to fight the germs used to create certain vaccines—especially those that use a live virus. While some vaccines may be risky for children with PI, others may be beneficial.
How do you know if a vaccine will help or harm your child? According to physicians, it depends upon the type of immunization, the type of treatment your child is receiving, and the specific PI disease.
How Vaccines Work
Vaccines use a harmless form of a germ to ‘trick’ the immune system into believing that the body is being invaded by disease. Vaccines stimulate the immune system into producing antibodies, a protein in the blood that helps to strengthen immunity. Immune cells such as the B and T cells play an important role in helping the body to fight disease. Each type of immune cell has a specific role. For example, B cells form plasma cells that secrete antibodies, which help to:
- Neutralize toxins
- Aid white cells in destroying germs
- Group viruses together
- Activate the complement system, comprised of 20 proteins important in immunity and inflammation
- Produce memory cells to help the body fight future infection
T cells secrete powerful chemicals called cytokines that in turn stimulate B cells and control inflammation and healing. Some T cells turn into killer cells, directly attacking cells that have been infected by virus.
Different Immune Diseases
For each of the over 150 types of immune disease,1 the response to vaccinations may be different. For example, children with B cell problems cannot respond to vaccines by making an antibody. A child with Severe Combined Immune Deficiency will not benefit from any vaccines and could be harmed if given a live virus or bacterial vaccine. However, a child with Partial DiGeorge Syndrome will respond to most vaccines. Children with defects in other parts of the immune system, such as Chronic Granulomatous Disease, can respond normally and should be immunized. Be sure to check about benefits and risks of each vaccine for your child’s specific immune disease.
No Live Vaccines
Children with PI lack the immune defenses necessary to fight certain vaccines. They should not, for example, receive any form of live virus or bacteria vaccine, including measles, mumps, BCG, chicken pox (varicella)2,3 and the nasal vaccine for influenza, FluMist. In addition, family members or caregivers of PI patients should not receive live virus vaccines because they might spread the virus to the child with PI. It’s also important for children with PI to avoid contact with others who may have received a live vaccine.
Unlike live vaccines, vaccines that have been killed do not pose as high a risk to children with PI. For example, the killed influenza vaccine is a safe alternative to the live flu vaccine, as are other forms of killed vaccines.
Role of IVIG and SubQ Infusions
If your child is receiving intravenous immunoglobulin (IVIG) or subcutaneous immunoglobulin (SCIG), please note that passive transfer of antibodies may transiently impair the immune responses to live attenuated virus such as mumps, rubella and varicella for up to 6 months and for a year or more to measles (rubeola). You should inform the immunizing physician if you or your child has recently received therapy with IVIG or SCIG so that appropriate precautions can be taken.4
Talk to Your Healthcare Professional
Researchers are constantly developing vaccines to prevent new and emerging diseases. Use of these and other vaccines in children with PI must be determined on a case-by-case basis.
For more information about vaccines and primary immune deficiency, talk to your physician.
- Geha R, Notarangelo L, Casanova JL, Conley ME, Chapel ME, Fischer A, Hammerstrom L, Nonoyama S, Ochs H, Puck J, Roifman C, Seger R, Wedgwood J. Primary immunodeficiency diseases: an update from the International Union of Immunological Societies Primary Immunodeficiency Diseases Classification Committee Meeting. Journal of Allergy and Clinical Immunology 2007; 120(4):776-794.
- National Institutes of Child Health and Human Development. National Institutes of Health. When the Body’s Defenses are Missing: Primary Immunodeficiency. NIH Pub No. 99-4149: p17.
- Winklestein JA, Winklestein ML, editors. Patient & Family Handbook for Primary Immunodeficiency Diseases, Third Edition. Towson, Md.: Immune Deficiency Foundation: 2002: pp27-28, 39.
- GAMMAGARD LIQUID [Immune Globulin Infusion (Human)] 10% [package insert]. Westlake Village, CA. Baxter International Inc.; July 2011.