【medical-news】JNCI:尽早接种四价人乳头状瘤病毒疫苗能使其有效性最大化
BackgroundIncidence of condyloma, or genital warts(GW), is the earliest possible disease outcome to measure when assessing theeffectiveness of human papillomavirus (HPV) vaccination strategies. Efficacytrials that follow prespecified inclusion and exclusion criteria may not befully generalizable to real-life HPV vaccination programs, which target abroader segment of the population. We assessed GW incidence after on-demandvaccination with quadrivalent HPV vaccine using individual-level data from theentire Swedish population.
MethodsAn open cohort of girls and women aged 10 to44 years living in Sweden between 2006 and 2010 (N > 2.2 million) was linkedto multiple population registers to identify incident GW in relation to HPVvaccination. For vaccine effectiveness, incidence rate ratios of GW wereestimated using time-to-event analyses with adjustment for attained age andparental education level, stratifying on age at first vaccination.
ResultsA total of 124 000 girls and women werevaccinated between 2006 and 2010. Girls and women with at least one university-educatedparent were 15 times more likely to be vaccinated before age 20 years thangirls and women whose parents did not complete high school (relative risk ratio= 15.45, 95% confidence interval [CI] = 14.65 to 16.30). Among those aged olderthan 20 years, GW rates declined among the unvaccinated, suggesting that HPV vaccineswere preferentially used by women at high risk of GW. Vaccination effectivenesswas 76% (95% CI = 73% to 79%) among those who received three doses of thevaccine with their first dose before age 20 years. Vaccine effectiveness washighest in girls vaccinated before age 14 years (effectiveness = 93%, 95% CI =73% to 98%).
ConclusionsYoung age at first vaccination is imperativefor maximizing quadrivalent HPV vaccine effectiveness.
