Effectiveness of HPV Vaccine Shown by Comparing Women Born in Different Decades

The vaccine for human papillomavirus (HPV) was recommended for routine use starting in 2006 for young women aged 9 to 26 years old. To assess the effectiveness of the vaccine, a study published in JAMA Health Forum compared the probability of women born in the 1980s and 1990s being diagnosed with HPV. The researchers found that women born in the 1990s were at a lower risk of HPV.

Data from 2 cycles of the National Health and Nutritional Examination Survey (2005-2006 and 2015-2016) were used for this study. Infection prevalence of HPV types 16 and 18 were estimated. Data analyses were performed.

There were 2698 women aged 18 to 26 years (mean [SD] age of 21.5 [2.7] years) and 32% White. Prevalence of HPV-16/18 was significantly lower in women born in the 1990s (5.6%; 95% CI, 4.0%-7.2%) compared with the women born in the 1980s (12.5%; 95% CI, 10.2%-14.7%).

At least half of each smaller age group had received 1 or more doses of the HPV vaccine in the 2015-2016 cycle (55% in those aged 18 to 20 years; 52% in those aged 21 to 23 years; and 50% of those aged 24 to 26). Prevalence of HPV decreased from the cycle before vaccination introduction in 2005-2006 (15.2%; 95% CI, 11.2%-19.1%) to 2015-2016 (3.3%; 95% CI, 1.3%-5.3%). Unvaccinated individuals had a 5.1% prevalence (95% CI, 1.2%-9.1%) and vaccinated individuals had a 1.0% (95% CI, 0.0%-2.5%) prevalence.

Women born in the 1990s had a 54% lower estimated probability of HPV-16/18 (6.3%; 95% CI, 5.7%-6.9%) compared with those born in the 1980s (13.6%; 95% CI, 12.7%-14.4%). The 2015-2016 cycle saw a 78% lower probability (3.5%; 95% CI, 2.9%-4.1%) compared with the 2005-2006 (15.7%; 95% CI, 14.0%-17.4%); the probability was 60% lower in unvaccinated women (6.3%; 95% CI, 5.0%-7.4%) and 92% lower for vaccinated women (1.2%; 95% CI, 1.0%-1.3%).

This study was limited by the self-reported reports of HPV vaccination status and also the exclusion of other types of HPV that were not covered by the vaccine.

The researchers concluded that HPV infection in women was lower in those born in the 1990s and in the post-vaccination period (2015-2016) across all demographics when compared with those born in the 1980s and women from the prevaccination cycle (2005-2006).

Reference

Shahmoradi Z, Damgacioglu H, Montealegre J, et al. Prevalence of human papillomavirus infection among women born in the 1990s vs the 1980s and association with HPV vaccination in the US. JAMA Health Forum. 2022;3(8):e222706. doi:10.1001/jamahealthforum.2022.2706