Parents can have confidence about the safety of the standard childhood vaccine schedule, a report from a panel of experts says.
The Institute of Medicine, which advises the government on health, looked into the vaccine schedule because of concerns from some parents that children today receive too many vaccines too soon.
Yet delaying shots prolongs the time babies and children are vulnerable to "devastating diseases," says co-author Pauline Thomas, associate professor of preventive medicine at New Jersey Medical School.
"There is ample evidence that it's not safe not to follow the schedule," Thomas says.
Some parents say the vaccine schedule is too crowded. Under the recommended plan from the Centers for Disease Control and Prevention, children today are vaccinated against 14 infectious diseases; they receive up to 24 vaccines by their second birthday and up to five in one visit.
Julie Punishill, a mother of two who lives in Connecticut, said she spaces out her children's vaccines whenever possible instead of following the CDC's advice of multiple shots at once.
"Both my girls were completely vaccinated with everything they needed by the time they entered kindergarten," Punishill says. "At times this would mean monthly visits to the pediatrician's office, but I would do it again this way in a heartbeat."
Though earlier reports from the Institute of Medicine focused largely on the safety of individual vaccines, this is the first to take a comprehensive look at the safety of the entire schedule, Thomas says.
Although 90% of children are fully vaccinated by the time they enter kindergarten, up to 40% of parents skip or space out some of their children's shots, following alternative schedules because of concerns over safety and side effects, studies show. Some parents worry about individual vaccines, and others wonder about "overwhelming" the immune system, or the cumulative effect of getting so many shots.
Still, the CDC schedules the timing and doses of childhood shots through careful scientific testing to optimize children's immune response and protect them during the years when they are most vulnerable, says vaccine researcher Peter Hotez, father of an autistic child. Hotez wasn't involved in the report.
"The concept that you are going to overload a child's immune system by giving too many vaccines at once makes no sense," says Hotez, dean of the National School of Tropical Medicine at Baylor College of Medicine.
Daily life -- from crawling around the floor to petting a dog -- exposes babies to far more antigens, the proteins that stimulate the body to produce antibodies against diseases, than vaccines, he says.
Paul Offit, who developed a vaccine against rotavirus, says the Food and Drug Administration requires manufacturers to test new vaccines in combination with previously approved shots to make sure they are safe and effective.
Thomas says she hopes the report will reassure parents and encourage them to fully protect their children.
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