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

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.

For good information about immunizations please try the National Network for Immunization Information Web site.

Annette from Dublin, Calif. asks: I understand that the flu vaccine protects against a different strain of flu each year. What I would like to understand is how long is this vaccine effective in the body? Also, do you see a time when health insurance companies will require vaccines or will not pay for complications of diseases that could have been prevented or reduced due to a vaccine? Thank you.

Schaffner: Annette, the flu vaccine provides protection against three different strains of the influenza virus each year. Experts at the WHO and FDA do their best to predict which influenza viruses will be causing illness during the next winter, and the vaccine is constructed to protect against those strains.

Because the influenza virus has the ability to change from year to year, the vaccine has to be changed to keep up. That is why we need to get vaccinated against the flu every year.

I do not anticipate that medical insurance companies will require influenza vaccination or will decline payments for influenza or its complications.

Most medical insurance will cover influenza vaccine, but not all do. I wish that all medical insurance policies would pay for influenza vaccine (and other vaccines) so that it would make it easier for everyone to get protected.

Irma from San Diego, Calif., asks: My 10-year-old son is allergic to eggs. Should he have the flu shot?

Schaffner: Irma, if your physician has determined that your son has a genuine egg allergy, then he should not be given the influenza vaccine. Egg allergy is one of the very few medical contraindications to receiving influenza vaccine because the vaccine is made, in part, in eggs. You, your family and all who have contact with your son should be vaccinated so that you do not bring the influenza virus home to him.

Sue from Beaverton, Ore. asks: 'Why are they recommending the flu vaccine for all children? What has changed that they have changed their recommendations midseason? Please be specific. Thank you.

Schaffner: The CDC's advisory committee on immunization practices has recommended that all children, aged 6 months through 18 years, be vaccinated against influenza starting next fall to protect them during the 2008-2009 influenza season and beyond.

The advisory committee made this recommendation after two to three years of study. A number of considerations played a role:

· Children are in the age group in our society that gets the most influenza. Fortunately, they get over the disease rather easily — for the most part.

· However, there is a growing appreciation that young, healthy children can contract influenza and quickly be so sick that they have to be admitted into hospital intensive care units and be put on breathing machines. Sadly, some children are killed by influenza. So far in this influenza season, 22 children have been reported to have died of influenza. There is a growing determination that in the United States, in the 21st century, that our children should not die of influenza if an effective and safe vaccine is available that can offer some protection.

· The children at greatest risk of the complications of influenza are those with certain chronic conditions (heart and lung disease, diabetes, etc). They are not getting effectively vaccinated against influenza at present, even though there has been a recommendation to do so for some time. It is anticipated that by making the recommendation simpler ( vaccinate all children from 6 months through 18 years of age), those at greatest risk will become better protected in the future.

· Children are the greatest spreaders of the influenza virus in our communities. When they get infected, they excrete more virus than do adults and for a longer period of time. Thus, they are the great spreaders to adults around them — including parents, grandparents and others who may be at particular risk of complications of influenza. It is hoped that by protecting all the children that the circulation of the influenza virus in our communities will be reduced, thereby offering some protection to older adults and others who would be at risk of suffering the bad consequences of influenza (pneumonia, hospitalization and death).

· Each year, influenza in children closes schools, disrupts the education program, obliges parents to stay home and care for sick children (some parents lose wages), and causes visits to doctors' offices and hospital emergency rooms. Much of this distress, turbulence and cost (millions of dollars each year) could be averted by vaccinating all children against influenza.

· Last, it was acknowledged that this was a gigantic task. Thus, family doctors, pediatricians, public health departments and many others would need to organize to get this annual task accomplished. This will be neither easy nor quick. It will be done gradually — and should begin next influenza vaccination season, starting in September 2008 and going into January and February 2009.

The CDC's advisory committee conferred with many partner professionals about this. These included the American Academy of Pediatrics, the American Academy of Family Physicians, and the Society for Adolescent Medicine, among others. All agreed that it was time to start vaccinating all children against influenza.