The impact of human papillomavirus (HPV) vaccination on cervical cancer risk reduction in the US.

e22531 Background: High-risk human papillomavirus (HPV) causes most cervical cancers. Both HPV vaccination and cancer screening reduce cervical cancer risk. However, screening rates by HPV vaccination status are not reported in the US, reducing the ability to assess population-level protection against cervical cancer. Using nationally representative data, we modeled how population-level cervical cancer risk changes as screening rates vary among vaccinated and unvaccinated females. Methods: Female respondents aged 21-39 years who self-reported cervical screening and HPV vaccination status in the 2019 National Health Interview Survey (NHIS) were included. Those aged 40 years or over in 2019 were excluded due to eligibility guidelines based on HPV vaccine introduction in 2006. Up-to-date cervical screening was defined as a Pap test within the past three years for ages 21-39 years or any HPV testing within five years for ages 30-39 years. Individuals receiving at least one dose of the HPV vaccine were considered vaccinated. Using estimates from US-focused modeling studies for the reduction in cervical cancer risk from vaccination (85%) and screening (70%), we calculated case scenarios to demonstrate how vaccination status changes the effect of cervical screening on population-level risk reduction of cervical cancer. Results: In the 2019 NHIS survey, 4,000 female respondents aged 21-39 years reported cervical screening attendance and HPV vaccination status. Up-to-date screening in ages 21-25 (63.9%) was lower compared to other age groups (26-29 years: 81.5%; 30-34 years: 85.6%; 35-39 years: 82.1%). However, reduction in cervical cancer risk in ages 21-25 was 68.6% relative to an unvaccinated and unscreened population, which was similar to risk reductions in all other age groups (26-29 years: 73.1%; 30-34 years: 67.7%; 35-39 years: 62.1%), a benefit likely due to their higher level of vaccination (56.7% vs. 26-29 years: 49.9%; 30-34 years: 26.4%; 35-39 years: 14%). Conclusions: This study demonstrates the importance of considering vaccination status when evaluating the population-level impact of cervical screening uptake on cervical cancer risk. Efforts to reduce the burden of cervical cancer should continue to include both vaccination and screening. Including vaccination status in national surveillance datasets would help identify and target interventions within communities at higher risk.