More Than 1 in 10 Parents Don't Follow Vaccination Schedule
Researcher Predicts Continued Increase, Risk of Disease Outbreaks
Alternative Vaccination Survey: Perspective
Another expert sees reason for concern about the 13%. "People who refuse vaccines tend to be clustered geographically," says Saad Omer, PhD, MPH, MBBS, assistant professor of global health, epidemiology and pediatrics at the Emory University Schools of Public Health and Medicine and the Emory Vaccine Center.
That, in turn, can create what he calls a ''critical mass" of people to trigger a disease outbreak.
"There is a reason why there is a schedule," says Omer. "The risk of preventable disease is not constant. One of the reasons we give vaccines at a certain age is the children are vulnerable at a certain age."
Another problem, he says, is that as parents spread out the vaccinations, the risk of not completing the recommended ones increases.
The CDC maintains a schedule of recommended vaccines on its web site, www.cdc.gov/vaccines/recs/schedules/child-schedule.htm
Parents who decline vaccines often depend on so-called ''herd immunity," says Karlen Luthy, assistant professor of nursing at Brigham Young University, Provo. She has researched vaccination practices.
Under herd immunity, when a large part of the population has been vaccinated, it is thought to provide some protection for those who have not been vaccinated nor had the disease.
However, Luthy says herd immunity ideally is meant to protect children who can't get vaccinated -- due to being organ transplant recipients, for instance. When parents of children who could be vaccinated decide not to, she says, "we are putting the lives of some of these other children at risk."
Barbara Loe Fisher, co-founder and president of the National Vaccine Information Center, says the finding of more than 1 in 10 parents changing the schedule is not a surprise to her. Her organization, she says, encourages informed decision making about vaccines.
As the number of childhood vaccines rises, she says, today's parents are becoming more informed and educated. They are doing research on vaccines before deciding whether their child should get them.
Fisher says she is troubled by the conclusions of the researchers that strategies are needed to reduce concerns of parents. Instead, she says, pediatricians ''need to listen to the mothers, most of the time it's mothers, when they describe vaccine reactions."
Some people are more prone to these than others, says says. "Much more needs to be known about vaccine high-risk events."