Cervical Intraepithelial Neoplasia Rates in British Columbia Women: A Population-Level Data Linkage Evaluation of the School-Based HPV Immunization Program.

BACKGROUND: To understand real-world human papillomavirus (HPV) vaccine impact, continuous evaluation using population-based data is critical. We evaluated the early impact of the school-based HPV immunization program on cervical dysplasia in women in British Columbia, Canada. METHODS: Data linkage was performed using records from provincial cervical screening and immunization registries. Precancerous outcomes were compared between unvaccinated and HPV-vaccinated women born 1994-2005. Incidence rate, relative rate (RR), and vaccine effectiveness (VE), using unadjusted and adjusted Poisson regression of cytology (HSIL) and histopathology (CIN2, CIN3, and CIN2+) outcomes, were compared across vaccination status groups. RESULTS: Women who received a complete series of vaccine on schedule between age 9 and 14 years had an adjusted RR = 0.42 (95% confidence interval [CI], 0.31-0.57) for CIN2+ over 7 years of follow-up compared to unvaccinated women, resulting in a VE of 57.9% (95% CI, 43.2%-69.0%). Adjusted RR for HSIL was 0.53 (95% CI, .43-.64), resulting in a VE of 47.1% (95% CI, 35.6%-56.7%). CONCLUSION: Women vaccinated against HPV have a lower incidence of cervical dysplasia compared to unvaccinated women. Immunization between 9 and 14 years of age should be encouraged. Continued program evaluation is important for measuring long-term population impact.

Support for policy options to increase vaccination coverage in British Columbia, Canada: an electronic survey.

BACKGROUND: Motivated by concerns of inadequate vaccination coverage and the potential for outbreaks of vaccine-preventable diseases, Canadian provinces have been discussing, implementing and tightening policies requiring documentation of vaccination for school enrolment. We sought to understand the acceptability of 14 potential vaccination policy levers among parents and other adults in British Columbia. METHODS: A representative online panel of 1308 adults in BC was surveyed in April 2017. Respondents were representative of the BC population by sex, age, geographic residence and percentage of household with children younger than 19 years. We used Poisson regression to estimate predictors of policy endorsement. RESULTS: Most respondents (> 80%) held positive attitudes toward vaccination. Policies such as mandatory documentation of vaccination at school entry were supported by more than 75% of all respondents. Punitive policies, such as denial of child tax benefits for nonvaccination, were supported by less than 40% of respondents. In multivariable regression, respondents with positive attitudes toward vaccination were significantly more likely to strongly support all potential policies. Additionally, female respondents and respondents with postsecondary education were significantly more likely to strongly support policies involving additional requirements for parents. INTERPRETATION: Most adults in BC held favourable attitudes toward vaccination, and strong support existed for policies designed to support vaccination. This study provides evidence that most adults in BC are supportive of vaccination and, when presented with a wide range of options, would likely be supportive of information and requirement policy options designed to increase vaccination uptake.