BALTIMORE (FRONTLINE MEDICAL NEWS) Most families’ kindergarteners met the full vaccination requirements of their state in a 2013 national survey, although 17% of parents were notified that their children still needed vaccines to comply with state requirements.

Of those 17% of families, however, 7.5% claimed exemptions from their states’ vaccination requirements at school entry, according to a study conducted by Philip Smith, Ph.D., and his associates at the Centers for Disease Control and Prevention.

Using data from the 1,465 parents who participated in the 2013 National Immunization Survey–Kindergarten (NIS-K,), Dr. Smith and his colleagues found that among the required vaccines, full coverage (five or more doses) was lowest for the DTaP vaccine, at 88.5% of 5- to 7-year-olds. Next was the varicella vaccine, with 89.4% of children having received at least two doses. For the inactivated polio vaccine, 90.9% of children had received at least four doses. The highest rate of full coverage – 91.8% – was for the MMR vaccine.

Whether children attended public or private school didn’t make a difference in vaccination rates. However, for children who had not entered kindergarten, “vaccination coverage was significantly lower than coverage for children who had entered kindergarten,” at least in part because those children were younger than those who had entered kindergarten, said Dr. Smith.

Health insurance status did not make a difference in the likelihood that a family would receive notification that their kindergartener needed vaccinations, implying that the differences “may not be attributable to access to primary care,” wrote Dr. Smith, presenting his work at a poster session of the annual meeting of the Pediatric Academic Societies.

The number of parents overall who claimed an exemption was “really, really small,” said Dr. Smith, just 1.9% of all families surveyed. He noted that his work shows that most of the children who have not met their state’s full immunization requirements for school entry do not come from families who seek exemption from the requirements.

Limitations of the survey, said Dr. Smith and his colleagues, included the inability to determine vaccination rates at the precise time of kindergarten entry. “As a consequence, our estimates of differences in vaccination coverage that is associated with notification as of the date of school entry may underestimate the true differences,” they wrote. Also, the small sample size made it difficult to ascertain the proportion of parents who took exemptions from vaccination of their child for medical, religious, or philosophical reasons.

“While our findings show that national vaccination coverage at school entry was high and exemption levels were low, some children remained undervaccinated after the start of the school year despite efforts of school vaccination programs to notify parents about needed vaccines,” wrote Dr. Smith and his coauthors.

The NIS-K is conducted by the Centers for Disease Control and Prevention, where Dr. Smith is employed. Dr. Smith reported no relevant financial disclosures.

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