Population seroprevalence of human papillomavirus types 6, 11, 16, and 18 in men, women, and children in Australia.

BACKGROUND: Representative population-based data on human papillomavirus (HPV) epidemiology are important for public health decision making but are difficult to obtain. Seroepidemiology is a valuable tool, although the relationship between HPV infection and seropositivity is incomplete. METHODS: We obtained a large representative sample using residual diagnostic test serum samples obtained from individuals aged 0-69 years (1247 samples from male patients and 1523 samples from female patients) in Australia. Serum antibody levels to HPV types 6, 11, 16, and 18 were measured using an immunoassay. RESULTS: Overall, seroprevalence of HPV types 6 and 16 was higher than seroprevalence of HPV types 11 and 18. Among female patients, peak HPV seropositivity occurred among those who were 30-39 years of age for types 6, 16, and 18 (22%, 22%, and 10.5%, respectively) and among those who were 40-49 years of age for HPV 11 (11.8%). Among male subjects, peak HPV seropositivity occurred among those who were 40-49 years of age for types 6 and 11 (15.4% and 9.1%, respectively) and among those who were 50-59 years of age for types 16 and 18 (14.3% and 8.2%, respectively). No cases of HPV seropositivity were detected in individuals <10 years of age. CONCLUSIONS: Australian seroepidemiological data, showing differing age-specific patterns of HPV seropositivity in male and female patients, are likely to be generalizable to other developed countries and add to other data supporting completion of HPV vaccination before adolescence.

Safety and persistent immunogenicity of a quadrivalent human papillomavirus types 6, 11, 16, 18 L1 virus-like particle vaccine in preadolescents and adolescents: a randomized controlled trial.

OBJECTIVE: Administration of a quadrivalent HPV-6/ 1/16/18 vaccine to 16- to 26-year-old women was highly effective in preventing HPV-6/ 1/16/18-related cervical/vulvar/vaginal precancerous lesions and genital warts. As the risk of acquiring HPV significantly rises after sexual debut, HPV vaccines should have the greatest benefit in sexually naive adolescents. We evaluated the tolerability and immunogenicity of quadrivalent vaccine in males and females 9 to 15 years of age through 18 months postenrollment. METHODS: In this randomized, double-blind trial, 1781 sexually naive children were assigned (2:1) to quadrivalent HPV-6/11/16/18 vaccine or saline placebo administered at day 1 and months 2 and 6. Serum neutralizing anti-HPV-6/11/16/18 responses were summarized as geometric mean titers (GMTs) and seroconversion rates. Primary analyses were done per-protocol (subjects received 3 doses, had no major protocol violations and were HPV type-specific seronegative at day 1). Adverse experiences were collected by diary card. RESULTS: At month 7, seroconversion rates were > or =99.5% for the 4 vaccine-HPV-types. GMTs and seroconversion rates in boys were noninferior to those in girls (P < 0.001). At month 18, > or =91.5% of vaccine recipients were seropositive, regardless of gender. A higher proportion of vaccine recipients (75.3%) than placebo recipients (50.0%) reported one or more injection-site adverse experiences following any vaccination. Rates of fever were similar between vaccination groups. No serious vaccine-related adverse experiences were reported. CONCLUSIONS: In 9- to 15-year-old adolescents, the quadrivalent vaccine was generally well tolerated and induced persistent anti-HPV serologic responses in the majority of subjects for at least 12 months following completion of a three-dose regimen. The vaccine durability supports universal HPV vaccination programs in adolescents to reduce the burden of clinical HPV disease, particularly cervical cancer and precancers.