Researchers at the Centers for Disease Control and Prevention in Atlanta and the Department of Health and Human Services National Vaccine Program Office say a survey indicates some parents remain unpersuaded that all vaccines are safe or even necessary.
Lead author Allison Kennedy of the CDC says parents should receive thorough explanations as to why infant immunizations should occur before age 2.
"That is when children are very vulnerable to contracting severe disease," Kennedy says in a statement.
As to other concerns voiced by some parents about vaccine safety, she says, "There is no credible evidence that vaccines are associated with learning disabilities, including autism."
Using data from the 2010 HealthStyles survey, Kennedy and colleagues surveyed 376 households and examined parental vaccine behaviors, attitudes, concerns, and what sources of information they rely on to learn about vaccines.
Although 23 percent of parents report they had no concern about vaccines, most parents reported at least one question regarding children:
-- Suffering physical pain from shots,
-- Getting too many shots in one visit.
-- Getting too many vaccines before age 2.
-- Receiving vaccines containing unsafe ingredients.
Parents also questioned whether vaccines were tested enough, if they might cause chronic disease, or would be administered to prevent diseases their children were unlikely to get, the researchers say.
The findings are published in Health Affairs.
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