Adolescent vaccine coverage levels rose substantially over a four-year period, but still fell far short of 100%, according to CDC researchers.
From 2006 to 2009, the percentage of U.S. teens who received at least one tetanus/diphtheria vaccine climbed fivefold to 56%, reported Shannon Stokley, MPH, and colleagues at the CDC in Atlanta, in Pediatrics.
In that same time period, vaccinations for meningitis rose from 12% to 54%. And from 2007 to 2009, rates for at least one vaccination for human papillomavirus (HPV) increased in girls from 25% to 44%.
The time periods covered in this study corresponded to the years that the following three vaccines were added to the recommended adolescent schedule:
- Acellular pertussis in combination with tetanus and diphtheria toxoids (TdaP)
- Meningococcal conjugate (MenACWY)
- HPV in girls only
In 2006, the annual National Immunization Survey Teen (NIS-Teen) was launched to assess vaccination coverage in adolescents 13 to 17 years old. Stokley and colleagues analyzed data from this survey, which began publishing state-level results in 2008 after initially giving only national totals.
For each survey year, the authors calculated the percentage of adolescents were who up-to-date for at least one dose of TdaP and MenACWY vaccines plus all three doses of HPV vaccine. They also looked at the extent to which parents said healthcare providers recommended each vaccine.
The authors found that coverage for each vaccine increased steadily over time on a national level:
- At least one Td/TdaP: 60.1% in 2006, 72.3% in 2007, 72.2% in 2008, and 76.2% in 2009
- At least one MenACWY: 11.7% in 2006, 32.4% in 2007, 41.8% in 2008, and 53.6% in 2009
- At least one HPV: 25.1% in 2007, 37.2% in 2008, and 44.3% in 2009
- Three or more HPV: 17.9% in 2008 and 26.7% in 2009
However, they also found that coverage varied by state. For instance, coverage came in at more than 70% for Td/TdaP and MenACWY in several East Coast states including New Hampshire, Massachusetts, Pennsylvania, and Rhode Island. But for those same vaccines, coverage was less than than 70% for many Western states such as Arizona, California, Oregon, and Washington. No state had coverage of more than 70% for single-dose HPV vaccination.
Over time and nationally, the gap between actual coverage and potential coverage remained the same for MenACW, increased for HPV, and decreased for Td/TDaP. The authors stressed that more data over many years would be necessary to examine any temporal trends.
When parents were asked why a vaccination schedule was not followed, the top three reasons for skipping Td/TdaP and MenACWY vaccines were lack of knowledge about the vaccine, lack of healthcare provider recommendation, and a parental decision that the vaccine was unnecessary.
Parental lack of knowledge and a judgment that the vaccine was unnecessary were the two main reasons that HPV vaccination guidelines were not followed. Less frequently, parents cited lack of sexual activity among adolescents was also cited.
Finally, the percentage of respondents who said their healthcare provider did recommend vaccinations rose from 2007 to 2009, but the recommendations remained far from universal:
- Td/TdaP: 42.8% to 45.8%
- MenACWY: 24.6% to 30.6%
- HPV: 38.6% to 55%
Limitations to the study included the fact that the NIS-Teen survey only targeted households with a landline. Also, vaccinations histories were obtained from participants' healthcare providers, which may have led to underestimates of true vaccination coverage.
Stokely and colleagues asserted that there was room for improvement in adolescent vaccination coverage, which might be achieved with simultaneous administration of multiple vaccines, healthcare provider endorsement, and increased parental education and awareness.
Stokely and co-authors are employees of the CDC.
The authors reported no financial conflicts of interest.
- Reviewed by Robert Jasmer, MD Associate Clinical Professor of Medicine, University of California, San Francisco and Dorothy Caputo, MA, RN, BC-ADM, CDE, Nurse Planner