The UPCOMING flu season could be the start of something big.
Not "big" as in the severity of flu. By all accounts, this year's influenza vaccine should be more successful than last year's only partly effective one. And it's too early to tell whether the flu this season will be especially widespread.
We mean "big" in terms of a grand, new experiment in the nation's approach to preventing flu outbreaks -- a push to vaccinate children, who are not only hospitalized at high rates because of the flu but appear to be efficient disease carriers as well.
Over the last decade, public health officials have been expanding the recommendations on which age groups of children should get the flu shot. This year marks the first time in history that flu vaccination is recommended for everyone age 18 and younger, with the exception of infants 6 months old and younger.
The main question is: Will parents go for it?
Although most adults have been included in flu vaccine recommendations for years -- and still are -- the emphasis on stopping the spread of flu has clearly shifted from reducing deaths in the elderly to stopping the spread of flu among kids.
Physicians hope that vaccinating kids en masse will not only spare thousands of them from the aches and pains of flu, missed school days and hospitalizations, but also will hinder the spread of illness throughout the rest of society -- parents, grandparents, baby-sitters, neighbors, teachers, coaches, office workers, healthcare personnel, bus drivers, and on and on.
"This is the concept of herd immunity," says Dr. Stephen C. Aronoff, chairman of the department of pediatrics at Temple University in Philadelphia. "The more people you vaccinate, the less likely you are to see infection in people who are not vaccinated."
For example, a vaccinated child won't pick up the virus at school, bring it home to Mom and Dad, who then infect their co-workers, clients and any others with whom they come in contact, including elderly people. Children, because of their biology and their not-too-great hygiene, are germy little beings who have the potential to spread flu far and wide.
Flu vaccination guidelines made by the federal Centers for Disease Control and Prevention have undergone major revisions over the last 20 years as more evidence points to children as carriers of the disease. In 2004, a recommendation was added that babies age 6 months to 23 months be vaccinated. In 2005, the CDC tacked on vaccination for age 24 to 59 months (with the exception of some children with illnesses such as reactive breathing disorders).
The recommendation to add youths ages 5 through 18, announced earlier this year, is based primarily on the fact that children suffer disproportionately from flu. Roughly 1 in 100 kids with flu is hospitalized, and 75 to 150 children die each year of the disease. Death rates are much higher among those 65 and older, but the rates of hospitalization for children 2 and younger match those of the elderly, and children 2 to 5 have the highest rates of seeing a doctor or visiting the emergency room because of the flu. And overall, young people ages 5 to 18 have the highest rates of infection.
"There is a higher rate of infection with influenza in school-age children -- what we call the highest attack rate," says Dr. Jeanne Santoli, deputy director of the Immunization Services Division of the National Center for Immunization and Respiratory Diseases at CDC. "We know the vaccine is effective in this age group, and we know it's safe. So the recommendation is based on the direct benefit to these children. But there's another reason too. What does it mean to the community if we vaccinate these children?"
Vaccinating children could mean less flu all around, research suggests. From 1962 through 1987, most schoolchildren in Japan were vaccinated, and flu rates and deaths dropped significantly throughout the Japanese population.
In another example, officials in a small town in Michigan vaccinated schoolchildren at the start of the 1968 flu pandemic. The town had one-third the number of flu cases overall of nearby towns where children were not vaccinated.
Studies show that children are especially potent transmitters of the flu, says John Talarico, interim chief of immunization at the California Department of Health Services. Adults transmit flu germs for three to five days after symptoms first appear; children, about 10 days.
Expanding the pool of vaccine recipients is probably only part of the solution to curbing flu outbreaks, says Dr. Peter Szilagyi, a pediatrician and expert in child immunizations at the University of Rochester Medical Center in Rochester, N.Y.
"We also need more effective vaccines. I think the combination of those two things will really help."
In the meantime, the CDC will be monitoring outbreaks over the next several years to determine whether its push to immunize children reduces the nation's flu load.