YOU ASKED, WE ANSWERED: Answers to Your Flu Vaccine Questions

Dr. William Schaffner addresses your questions about the flu vaccine.

ByABC News
January 8, 2009, 12:05 AM

Feb. 28, 2008— -- Dr. William Schaffner answered our viewers' questions about the flu vaccine.

Schaffner is chairman of the department of preventive medicine at the Vanderbilt University School of Medicine. He is also a professor of infectious diseases. His primary interests are infectious diseases and their prevention. Schaffner has worked extensively on the effective use of vaccines in both pediatric and adult populations.

Betsy asks: Is there mercury in the shot....if so, how much?

Schaffner: The influenza vaccine shot comes in two forms: thimerosal (mercury)-free as well as with the preservative thimerosal. Multidose vials contain a small amount of the preservative. The nasal spray influenza vaccine also is preservative-free.

Maria asks: Is it safe for infants and preschoolers to receive a flu shot with thimerosal when thimerosal-free shots are not available?

Schaffner: Yes, it is safe for young children to receive a flu shot that contains thimerosal. My grandchildren did last year and again this year.

Laura asks: Our son received all his routine pediatric vacs and flu vacs until age 2 when he regressed developmentally and stopped speaking after the MMR. We recently found out he has a primary immune deficiency. How will this mandate affect children like him? He was not able to develop a protective level of immunity to any diseases he was vaccinated for except for measles, which we suspect his body is still harboring. With this mandate, I fear a well-meaning physician could require my son to get vaccinated and we could "lose" him again. How does this mandate take into consideration the individual needs vs. the herd mentality?

Schaffner: First, let's be clear: Yesterday's recommendation of the CDC's advisory committee on immunization practices is just that a recommendation. It is not a mandate (that is, a requirement). Second, please be assured that physicians will not give an immunocompromised child any vaccine that is not appropriate. When your son reaches kindergarten or school age, he will be provided a letter from your physician stating that he has a medical contraindication to at least some of the routine vaccines. This will be honored by the school, as all state laws requiring vaccines for school attendance have provisions for medical exemptions.

I am especially pleased with the action of the CDC advisory committee yesterday because if all the other children who have contact with your son are vaccinated, it will be much more difficult for the nasty influenza virus to find him and make him sick. That is the beauty of communitywide participation. By vaccinating all the strong, those among us who are somewhat frail will be protected because we will provide a "ring of prevention" around them.