Is vaccine type seropositivity a marker for human papillomavirus vaccination? National Health and Nutrition Examination Survey, 2003–2010

• We analyzed 2003–2010 National Health and Nutrition Examination Survey (NHANES) data of females aged 14–59 years.
• We evaluated seropositivity to vaccine types as a marker for HPV vaccine coverage.
• Vaccine type seropositivity was significantly higher post vaccine introduction.
• There was high agreement between seropositivity and report of HPV vaccination.

SummaryObjectiveSince 2006, human papillomavirus (HPV) vaccination has been routinely recommended for adolescent females in the USA. The quadrivalent vaccine induces long-term seropositivity to HPV 6/11/16, which may be useful as a marker for HPV vaccine coverage.MethodsWe evaluated vaccine type seropositivity (i.e., seropositivity to HPV 6/11/16 with or without HPV18) among females aged 14–59 years participating in the 2003–2010 National Health and Nutrition Examination Survey (cross-sectional, nationally representative surveys). We compared pre-vaccine era (2003–2006) to vaccine era (2007–2010) seropositivity and assessed agreement between vaccine era seropositivity and reported vaccination by kappa statistic.ResultsSeropositivity was 1.0% among 2151 females in the pre-vaccine era and 22.1% among 1420 females in the vaccine era (p < 0.001); 23.1% of vaccine era females reported receipt of one or more HPV vaccine dose. Seropositivity and reported vaccination had high agreement (kappa = 0.79; 95% confidence interval 0.74–0.84). Among seropositive females, 14.5% reported no vaccination.ConclusionThe increase in vaccine era seropositivity likely reflects vaccination uptake. Our study suggests seropositivity to HPV 6/11/16 may be a useful marker for vaccination coverage in adolescent and young adult females. Discordance between seropositivity and reported vaccination may be explained by inaccurate reporting and/or natural exposure to HPV.