Recent recommendations in coverage for adolescents aged 13–17 years have not yet reached the same levels of success as achieved in children aged 19–35 months, according to results from the most recent National Immunization Survey.
Adolescents aged 13–17 years—who were included in the Centers for Disease Control and Prevention survey for the first time—fulfilled the recommended immunizations at high percentages for measles, mumps, and rubella vaccine (87% for 13–15 years of age) and hepatitis B vaccine (82%).
But recommendations made in 2005 for vaccination with tetanus-diphtheria or tetanus, reduced diphtheria, and acellular pertussis vaccines (Tdap) and meningococcal conjugate vaccine (MCV4) reached levels of only 60% (after age 10 years) and 12%, respectively (MMWR 2007;56:885-8).
In contrast, the CDC estimated that the percentage of children aged 19–35 months who have received the recommended series of childhood vaccines grew from 76% in 2005 to 77% in 2006 (MMWR 2007; 56:880-5).
“While we're very pleased with how high the complete series coverage is, we know we still have a way to go to reach the 80% goal for [the Healthy People 2010 target] and the 90% coverage for individual vaccines,” Dr. Melinda Wharton, deputy director for the National Center for Immunization and Respiratory Diseases at the CDC, said during a teleconference on the survey results.
Any new vaccine recommended by the Advisory Committee on Immunization Practices has a target coverage of 90% or higher within 5 years of the recommendation, according to the CDC.
The survey did not report on human papillomavirus (HPV) vaccination because it was conducted before HPV vaccination recommendations were published.
The survey estimated immunization coverage through a quarterly, random-digit-dialed sample of telephone numbers in each of the 50 states, plus 30 local areas (counties and cities). The household responses are then corroborated with vaccination records from their health care providers.
The household response rates for the child and adolescent surveys were 65% and 56%, respectively.
The 21,044 children with provider-reported vaccination records represented 70% of all children with completed household interviews, whereas the 2,882 adolescents with provider-reported vaccination records represented 53% of adolescents with completed household interviews.
For children aged 19–35 months, the levels of coverage rose significantly from 2005 levels for pneumococcal conjugate vaccine (from 83% to 87%, for three or more doses), varicella vaccine (from 88% to 89%), and poliovirus vaccine (from 92% to 93%).
Across the states, the percentage of children who received the recommended series of childhood vaccines ranged from 84% in Massachusetts to 60% in Nevada. These rates also varied across local areas, ranging from 81% in Boston to 65% in Detroit.
Coverage for the recommended series of childhood vaccines was significantly lower for black children than white children (74% vs. 78%), but after adjustment for income the difference in coverage was no longer significant.
“Vaccination funding through the federal Vaccines for Children program has contributed to record coverage levels among children who are uninsured or underinsured, but additional measures are needed to deliver vaccines to children who live below the poverty level,” according to the CDC.
“Clearly we need to do more to get information to parents and health care providers, and to make sure that everyone has a good understanding of the recommendations and the health benefits that the vaccines provide,” Dr. Wharton said.
Dr. Wharton suggested that physicians can use immunization registries or electronic medical records to track the immunization status of individual adolescents and children. Such systems “can really be part of the solution because many children may move from provider to provider or community to community,” and may have already received vaccines even though it has not been recorded.