Despite national recommendations for HPV, tetanus booster and meningococcal vaccines,12
vaccination levels among adolescent females in these five North Carolina counties were suboptimal, with just 17% of parents indicating their daughters had received all three vaccines. To our knowledge, this represents the first estimate of having received all three of these recommended vaccines among adolescent females. The percentage of parents who reported their daughters had received tetanus booster vaccine was slightly below the Healthy People 2010 goal of 90% vaccine coverage (set for adolescents aged 13–15 years),14
and meningococcal and HPV vaccination levels were much lower.
HPV vaccine uptake in our study was highly similar to the 2008 NIS-Teen estimate for North Carolina (36% vs. 34%), as was meningococcal vaccine uptake (36% vs. 31%).13
However, tetanus booster vaccine uptake was noticeably higher in our study (87% vs. 64%).13
While the difference in tetanus booster vaccine uptake may be partly due to reliance on parental reports of daughters' vaccination histories (NIS-Teen estimates are based on provider records), we believe it is more likely due to the recent Tdap school requirements in North Carolina. Beginning in August 2008, the state required all 6th
grade students attending public schools (and 12 year olds in non-public schools) to receive a booster dose of Tdap, provided it had been five or more years since their last dose of Td.22
North Carolina also required individuals enrolling in a college or university for the first time on or after July 1, 2008 to receive a booster dose of Tdap, provided Td or Tdap had not been administered within the past 10 years.22
As data collection for this study occurred exclusively after these requirements went into effect (whereas NIS-Teen was conducted both before and after), our results may simply reflect the effectiveness of the new Tdap school requirements. School requirements do not currently exist in North Carolina for HPV or meningococcal vaccination.22
Interestingly, the correlates of vaccination were similar across the four outcomes examined in our analyses. Daughters whose parents indicated they had preventive care visits in the last year were often more likely to have received recommended adolescent vaccines. However, while most (83%) daughters had a preventive care visit in the last year, relatively few of these daughters had received all three vaccines, suggesting missed opportunities to vaccinate.23
Developing and implementing a standard of care and structured visits for adolescents, including an adolescent immunization platform,24
may decrease such missed opportunities. Physician vaccination reminder systems can also help increase vaccination levels,25,26
yet remain underused by healthcare providers.27
Furthermore, almost 20% of parents indicated their daughters did not have a preventive care visit within the last year, despite recommendations that all adolescents should have such visits annually.28,29
For these adolescents, alternative vaccination settings, such as school-based health centers, may be an option to consider for increasing vaccination.30
Adolescents who received one of the recommended vaccines examined in this study were often more likely to have received other recommended adolescent vaccines examined (e.g., receipt of tetanus booster vaccine was correlated with meningococcal vaccination). Concomitant administration of adolescent vaccines could capitalize on the tendency of adolescents who get one vaccine to also get others. ACIP currently recommends administering tetanus booster and meningococcal vaccines during the same healthcare visit if both are indicated and available.10
ACIP also currently states that HPV vaccine can be administered at the same visit as other adolescent vaccines, because concomitant administration is likely to increase the number of adolescents receiving vaccines on schedule.11
Although parents and healthcare providers have expressed concerns about concomitant administration of childhood vaccines,31,32
most parents have allowed their children to receive multiple recommended vaccines during the same visit.33
Additional research on the acceptability of concomitant administration of adolescent vaccines to both adolescents and parents is needed.
Vaccination tended to be lower among younger adolescents in our study, even though all three vaccines have the same target age group of 11–12 year-old adolescents. Other studies have also reported lower levels of HPV and meningococcal vaccination among younger adolescents.15,34
While some unvaccinated 11–12 year olds may have not yet had the opportunity to receive all three vaccines but will eventually receive them, it is concerning that many may not. About one-third of all pertussis cases occur among 11–18 year olds,10
and adolescents ages 11–19 years have rates of meningococcal disease higher than the general population.6
College students living in dormitories also face high rates of meningococcal disease.6
About 9% of females ages 14–19 years have serologic evidence of infection with at least one HPV type contained in the quadrivalent vaccine.35
Increasing vaccination among younger adolescents may help reduce the prevalence of these diseases among adolescents.
Our study has several important strengths including interviewing a large sample of parents, examination of three recommended adolescent vaccines, and a good response rate. While our assessment of vaccination relied on parental reports that may be subject to recall and social desirability error, previous research has shown parents can accurately recall their young children's influenza vaccination status.36
Furthermore, HPV and meningococcal vaccine uptake was comparable to estimates from the 2008 NIS-Teen, as discussed previously.13
We did not collect information regarding which meningococcal (MPSV4 or MCV4) or tetanus booster (Tdap or Td) vaccines adolescents received, the timing of vaccine delivery, or the presence of existing conditions that may contraindicate vaccination. We also did not collect information on some constructs that may be important to vaccination behaviors or specific reasons why daughters had not received all vaccines. Since we interviewed parents from only one geographic region who had a landline telephone and spoke English, the generalizability of the findings to populations that have different characteristics is not yet known.
Vaccination coverage among adolescent females was suboptimal, with few parents indicating their daughters had received all three recommended adolescent vaccines: tetanus booster, meningococcal and HPV vaccines. Ensuring annual preventive care visits and reducing missed opportunities for vaccination at existing visits, perhaps by increasing concomitant administration of adolescent vaccines, may help increase vaccine uptake.