Prevalence of Human Papillomavirus Infection Among Women Born in the 1990s vs the 1980s and Association With HPV Vaccination in the US

This cross-sectional study examines rates of human papillomavirus infections among a cohort of vaccinated and unvaccinated women born in the 1990s.


Introduction
In the US, human papillomavirus (HPV) vaccination was first recommended for routine use among girls and young women (9-26 years old) in 2006. 1 Steady improvements in HPV vaccination coverage during the past decade may have translated into protective benefits among the contemporary birth cohort (ie, women born in the 1990s compared with the 1980s).To measure whether HPV vaccination has been associated with reduced infection rates among recently born vaccinated women (vaccine-mediated immunity) and unvaccinated women (herd protection), we compared HPV prevalence in the 1980s vs the 1990s birth cohorts and a prevaccination period vs a recent period.

Methods
The institutional review board of The University of Texas Health Science Center deemed this study exempt from review and waived the requirement for informed consent because only publicly available data were used.We followed the Strengthening the Reporting of Observational Studies in history and race and ethnicity were self-reported and collected by trained interviewers during a home interview.Participants provided self-collected cervicovaginal swab specimens that were evaluated by a polymerase chain reaction test and followed by type-specific hybridization.Detailed survey questionnaire, sample collection, and laboratory methods are available elsewhere. 2   We estimated infection prevalence of HPV types 16 and 18 (HPV-16/18)-the oncogenic types covered by 4-valent vaccine-for 2 birth cohorts: women born in the 1980s (1980)(1981)(1982)(1983)(1984)(1985)(1986)(1987)(1988)(1989) and the 1990s (1990)(1991)(1992)(1993)(1994)(1995)(1996)(1997)(1998).To estimate HPV vaccination effectiveness, we estimated the prevalence of HPV-16/18 infection before vaccine introduction (2005)(2006) and recently (2015-2016) from the NHANES data.Considering that the 1990s birth cohort was 26 years old or younger in 2015 and 2016, we limited the comparison to the 18-to 26-year-old age groups.In addition, we conducted a multivariable logistic regression to assess differences in estimated probabilities, with simultaneous adjustments made for the number of vaccine doses, age, race and ethnicity, country of birth, age at sexual debut, and the number of lifetime sex partners.
Data analyses were performed from November 2021 to February 2022 with SAS, version 9.4 (SAS Institute Inc) using the SAS PROC SURVEY procedures, 3 which included weight, cluster, strata, and domain statements.Statistical significance was tested at 2-sided P < .05.

Figure .
Figure.Prevalence Estimates of HPV-16/18 Infection Among Women Born in the 1980s and 1990s and During the Prevaccination Period (2005-2006) vs the Recent Vaccination Period (2015-2016), Overall and by HPV Vaccination Status

a
The final analytical sample for panel A consisted of women 18-32 years old born in the 1980s (n = 2458) and 1990s (n = 1280).

Table ) .
Similarly, the The estimated probabilities were lower for the 1990s (vs 1980s) birth cohort and for the recent (2015-2016) vs the prevaccination (2005-2006) period across race and ethnicity, lifetime number of sex partners, and country of birth categories.