Measuring the impact (such as reduction in HPV-related precancers) of the HPV vaccine on health outcomes is a critical but challenging public health priority. Of highest importance is the impact of the vaccine on reducing the burden of cervical cancer, which is the most common HPV-related cancer in women. However, since it takes many years for HPV infection to progress to invasive cancer, measuring vaccine impact on cervical cancer is difficult and can take decades. Instead, we can monitor high-grade cervical lesions that are likely to progress to invasive cancer if left untreated as early indicators of vaccine impact. In this surveillance project, we monitor these cervical lesions among women age 18 and older in five different communities around the United States.
We collect demographic and clinical information from laboratory and medical records for every woman who has a high-grade cervical lesion identified. For women aged 18-39 years who have a high-grade cervical lesion identified, we collect additional information, such as insurance, cervical cancer screening history, and vaccination history. Additionally, archived tissue specimens are obtained and sent to CDC for HPV type testing for 37 HPV types, including those targeted by HPV vaccines. For more detailed information on the HPV-IMPACT study methods, click here.
The main objectives of HPV-IMPACT are to:
- Monitor trends in overall incidence of high-grade cervical lesions over time in women aged 18-39 years;
- Monitor prevalence and distribution of HPV types in women aged 18-39 years with high-grade cervical lesions;
- Describe the demographic, clinical, and HPV type characteristics among patients with high-grade cervical lesions;
- Estimate and monitor trends in cervical cancer screening among residents of the catchment areas; and
- Estimate the proportion of patients with high-grade cervical lesions who received the HPV vaccine, and estimate vaccine effectiveness.
The HPV-IMPACT project is a collaboration between two groups at CDC: the Viral Vaccine Preventable Diseases Branch in the Division of Viral Diseases, and the Chronic Viral Diseases Branch in the Division of High-Consequence Pathogens and Pathology.
Learn more about HPV-IMPACT surveillance areas and partners.