Vaccine FAQ

Q: Will too many shots overload my child’s immune system?

One parent observed that in the span of a few hours a North American child may eat her own nasal discharge, kiss the dog on the lips, taste the handrail at the airport, and still be able to survive quite nicely. The immune system is remarkably robust.

Careful and thorough studies done under the watchful eye of the FDA have shown that many vaccines can be given on the same day without a decrease in effectiveness or an increase in side effects. The same natural immune system that protects us from the multitude of personal microbiologic indiscretions of childhood is quite well equipped to protect us from a few vaccines.

Q: Aren’t some infectious diseases necessary to strengthen a child’s immune system?

No. If a person could go through life without a single infectious disease, his immune system would not have diminished. Exposure to deadly diseases like Hib, polio, pertussis and measles is not vital to a strong immune system!

Q: Isn’t disease just a natural part of life, while vaccines are unnatural and man-made?

Yes, but by the same token, disease and death are a natural part of life. Because vaccines are man-made, they defy nature, but they also prolong the lives of infants, making infant mortality rates plummet and life expectancies soar.

Q: Should I wait to vaccinate my child until he has recovered from being sick and his immune system is stronger?

Your child’s immune system is just as strong during most common minor illnesses as at other times, but he should not be given vaccines during a moderate to severe illness. This is because side effects of the vaccine (especially fever) may confuse the doctor regarding the course and management of the illness. Minor illnesses are not a reason to delay a vaccination.

Q: Is the immune system down for a while after receiving a vaccine?

A portion of your immune system (not the part that makes antibodies) may be depressed for as much as four weeks after live injected vaccines like measles, mumps, rubella, or chickenpox. You aren’t more likely to get a serious infectious disease during those four weeks, but it is recommended that you hold off on getting another live, injected vaccine during that time.

Q: A 4-month-old infant may receive five different vaccines (hepatitis B, Hib, polio, DTaP, pneumococcal) at one office visit. Is it safe to give so many vaccines at such a young age?

The FDA tests vaccines that are given at the same time to be sure there is not an increase in side effects or a decrease in vaccine effectiveness. Each of the five vaccines has been tested in this way.

Q: Aren’t children naturally protected from these diseases by the immunity they get from their mothers? How long does this immunity last?

Antibodies are passed from the mother to the fetus toward the end of pregnancy. These antibodies are an important source of protection from some diseases (such as measles), but not from others (such as polio). For full-term infants, these antibodies may last 6 to 18 months; the length of time varies. Severely premature infants are born without the mother’s antibodies.

Q: Won’t the actual disease, versus the vaccine, give my daughter a higher antibody level, so her own children will have immunity longer?

This is true for some but not all diseases. A mother’s antibodies give good protection against some diseases (such as measles), but not others (such as polio).

If a girl gets measles, she will probably have a higher antibody level than girls whose antibody levels are a result of vaccination. When she is having children, she will pass along a greater amount of measles antibody, so her infant may be immune to measles longer than the infants of vaccinated mothers. This makes it more important to have an infant immunized with measles vaccine at 12 to 15 months of age.

Of course, a particular infant may have nonprotective antibody levels even if born to a woman who had the disease. Unless you do blood tests, it is impossible to be sure of an infant’s immunity, so keep very young children away from anyone with measles, chickenpox, and so forth.

Q: Won’t the actual disease give my child lifelong immunity, whereas the vaccine will wear off?

You can get some diseases-like tetanus-more than once, but once you have had most diseases you have lifelong immunity. You need to get some vaccines-like diphtheria and tetanus-periodically to stay completely protected, but you need only one injection of others (like measles vaccine) for lifelong immunity. In general, diseases are better at giving you lifelong immunity, but their disadvantage is that you might have to suffer through the disease and its complications (and possibly die) to become immune.

This information is excerpted from the book Vaccinating Your Child: Questions and Answers for the Concerned Parent (Peachtree Publishers, Ltd., 2000). The book’s authors are Dr. Sharon G. Humiston, a pediatrician and clinical researcher at the CDC and the University of Rochester, and Cynthia Good, an award-winning journalist and host of the television show “Good for Parents”.