Ancillary Benefit of Increased HPV Immunization Rates Following a CBPR Approach to Address Immunization Disparities in Younger Siblings.

Increasing HPV vaccination rates may decrease the disproportionately high HPV-associated disease incidence and mortality in African Americans (AA) and lower socioeconomic individuals. Data from a community-based participatory research (CBPR) study addressing immunization disparities among 19-35 month old children was analyzed to identify ancillary benefits in HPV immunization rates for adolescent siblings. Sub-study analysis inclusion criteria: AA (N = 118), 13-17 years old, younger sibling enrolled in parent study, and enrolled ≥ 9 months. Parent/caregiver interventions included: a web-based immunization toolkit with information on age-appropriate vaccines; a multimedia community outreach campaign; and reminder mailings. HPV up-to-date (UTD) status was defined as Wisconsin Immunization Registry (WIR) documentation of at least three HPV vaccines. McNemar's test compared pre/post intervention HPV status. Two dependent proportions testing compared the proportion of adolescents that became UTD in the study cohort, City of Milwaukee, and State of Wisconsin. Parents/caregivers perceived that 92% of adolescents were HPV-UTD, while only 24% had a WIR-verified HPV-UTD status. Baseline UTD status of the younger siblings 19-35 month old 4:3:1:3:3:1:4 antigen series was 63%, which increased to 86% at study completion. Adolescent's HPV-UTD immunization status increased from 30 (25%) at enrollment to 54 (46%) at study completion [p = 0.004]. A statistically significant larger proportion of adolescents became HPV-UTD in the study cohort (20%) compared to the City of Milwaukee [14%, p = 0.042] and the State of Wisconsin [14%, p = 0.046]. A culturally-tailored CBPR approach targeting parents/caregivers of younger AA children can have significant ancillary benefit to increase HPV immunization rates in adolescent siblings.