Statewide Surveillance for Human Papillomavirus Vaccine Impact in Connecticut

Background: While the human papillomavirus (HPV) vaccine has proven nearly 100% efficacious in clinical trials, it is important to monitor HPV-associated precancerous lesions in order to determine vaccine effectiveness at the population level. 

Objectives: To present results from the first year of statewide surveillance in Connecticut (CT) for cervical intraepithelial neoplasia grades 2 and 3 (CIN 2, 3) and adenocarcinoma in situ (AIS).

Methods: Reports from all pathology laboratories were analyzed with descriptive statistics.

Results: A total of 2,992 women with CIN 2, 3 or AIS were reported in 2008.  The median age of case patients was 27 years.  The greatest burden of disease was among women ages 20–24 years (28.6% of cases) and women ages 25–29 years (22.4% of cases).  The overall rate for these diagnoses in CT was 196 per 100,000 adult female population.  Rates were highest among women ages 20–24 and 25–29, at 701 and 615 cases per 100,000, respectively.  Overall, women in urban areas (cities >100,000 population) had a 30% higher rate of precancerous lesions than non-urban women (262 vs. 201 per 100,000); however urban women ages 15–24 years had a 22% lower rate compared to non-urban women (435 vs. 557 per 100,000).

Conclusions: These data indicate that CIN 2, 3, and AIS disproportionately affect young women in CT with the highest rates reported for those ages 20–29 years and those living in urban areas.  Understanding reasons for lower rates among younger urban women requires further study.

Implications for Programs, Policy, and/or Research: Population-level impact of HPV vaccine in reducing HPV-associated precancerous lesions may be detected soon given the high burden of disease and the young age of cases.  Current catch-up vaccination efforts should focus on adolescents and women living in higher rate areas (urban) of the state.