HPV serotypes included in the quadrivalent vaccine, or 4vHPV, decreased 86% among adolescents aged 14 to 19 years a decade after its introduction in the United States, according to research published in The Journal of Adolescent Health. Researchers wrote that a 71% decrease also occurred among those aged 20 to 24 years.
“Three highly effective HPV vaccines are recommended by WHO: bivalent, quadrivalent and nine-valent vaccines,” Nancy M. McClung, PhD, RN, an epidemiologist at the CDC’s National Center for Immunization and Respiratory Diseases, told Infectious Diseases in Children. “All HPV vaccines target the most common cancer-causing HPV types: HPV 16 and 18. Types 16 and 18 cause 70% of cervical cancers and the majority of other anogenital cancers caused by HPV. Efforts to increase HPV vaccination and to introduce HPV vaccine in low-income countries that do not yet have HPV vaccination programs are the most important ways to reduce cancers caused by HPV globally.”
McClung and colleagues assessed the prevalence of HPV DNA in patients aged 14 to 34 years who took part in the National Health and Nutrition Examination Survey (NHANES) before and after the vaccine was introduced in 2006.
Of those in the NHANES survey, 4,674 female participants had HPV typing results. Adolescents aged 14 to 19 years had a vaccination coverage of 53.9% with one or more doses of 4vHPV. Coverage was highest among Mexican Americans (59.5%), followed by non-Hispanic blacks (58.1%) and non-Hispanic whites (52.6%). For those aged 20 to 24 years, vaccine coverage was 58.8% for non-Hispanic white patients, 45% for non-Hispanic black patients and 33.8% for Mexican American patients.
The researchers noted that the prevalence of serotypes included in 4vHPV among adolescents aged 14 to 19 years across all demographics decreased from 11.5% to 1.8% after the vaccine was introduced (adjusted prevalence ratio [PR] = 0.14; 95% CI, 0.08-0.24). Decreases were also identified among non-Hispanic whites (PR = 0.14; 95% CI, 0.06-0.29), non-Hispanic blacks (PR = 0.26; 95% CI, 0.12-0.54) and Mexican Americans (PR = 0.13; 95% CI, 0.3-0.53).
Further, the prevalence of 4vHPV serotypes decreased from 18.5% to 5.3% (aPR = 0.29; 95% CI, 0.15-0.56) among participants aged 20 to 24 years, with decreases noted among non-Hispanic whites (PR = 0.27; 95% IC, 0.11-0.67) and non-Hispanic blacks (PR = 0.38; 95% CI, 0.18-0.8).
According to the researchers, no significant decreases in 4vHPV serotypes occurred in older age groups.
“Increasing the number of girls and boys who receive routine HPV vaccination at age 11 or 12 years is the most important way to further reduce HPV prevalence among youth,” McClung said. “Providers can incorporate practical and proven strategies to increase vaccination rates. Two of these strategies include recommending the HPV vaccine in the same way and the same day as other adolescent vaccines and learning how to effectively answer some of parents’ most common questions.” – by Katherine Bortz
Disclosures: The authors report no relevant financial disclosures.
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