Post-vaccination anti-human papillomavirus antibody seroprevalence among Czech teenaged girls and women

Objective To evaluate seroprevalence among Czech girls and women previously vaccinated against human papillomavirus (HPV). Methods A commercial enzyme-linked immunosorbent assay was used to determine the level of antibodies and seropositivity, with no genotype specification. Results A group of 356 teenaged girls and women with a mean age of 19.5 years (95% confidence interval [CI], 18.9–20.1 years) was found to have 94.1% HPV seropositivity (95% CI, 91.1%–96.3%) up to 3.5 years after vaccination. The vaccine-specific total seropositivity rates were 98.0% and 85.0% among quadrivalent vaccinees (Gardasil; Merck, Whitehouse Station, NJ, USA) and bivalent vaccinees (Cervarix; GlaxoSmithKline, Brentford, UK), respectively. Adjusting for age and post-vaccination time period, an expected 2:1 (quadrivalent:bivalent) ratio of the geometric mean concentrations of total HPV-specific antibodies induced by the vaccines was observed. The antibody avidity remained almost unchanged up to 3.5 years later. Nevertheless, the mean avidity index was significantly higher among quadrivalent vaccinees (2.50 M GuHCl/mL; 95% CI, 2.42–2.58 M GuHCl/mL) than bivalent vaccinees (2.09 M GuHCl/mL; 95% CI, 2.01–2.17 M GuHCl/mL). Conclusion High anti-HPV seroprevalence at a level related to the valency of vaccine used was achieved among Czech teenaged girls and women up to 3.5 years after vaccination.