Completeness of Reporting of Chronic Hepatitis B and C Virus Infections — Michigan, 1995–2008

Chronic hepatitis B virus (HBV) and chronic hepatitis C virus (HCV) infections are leading causes of death from cirrhosis and hepatocellular carcinoma in the United States. Because underreporting has complicated the understanding of disease burden, in 2010 the Institute of Medicine requested that CDC perform a comprehensive evaluation of national viral hepatitis surveillance. Hepatitis surveillance data rely on local and state estimates, and a better understanding of reporting at these levels can inform strategies to improve national data quality. As an initial assessment, CDC partnered with the Michigan Department of Community Health (MDCH) and an urban health-care system in southeastern Michigan to evaluate the completeness of reporting (including case status, demographic, and risk factor information) of cases of chronic HBV and HCV infection among persons who were enrolled in a multicenter chronic hepatitis cohort study to the MDCH viral hepatitis registry. This report summarizes the results of that assessment. Among clinically confirmed chronic hepatitis infections, 82% of HBV infections and 65% of HCV infections were reported. Completeness of reporting of chronic HBV and HCV infections was significantly improved for those with more recent clinical diagnoses, but reporting still remained incomplete. The completeness of reporting varied significantly by demographic characteristics of patients with HCV infection. Few reports of either HBV or HCV infection included risk factors. Improving surveillance of chronic hepatitis in Michigan will require exploration of more efficient methods for the transfer of laboratory and clinical data and evaluation of the most appropriate sources for risk factor information to aid in the prevention of viral hepatitis transmission. Similar collaborations with health-care institutions that use electronic International Classification of Diseases, Ninth Revision (ICD-9) codes and laboratory data can provide local and state health departments with insight into the challenges to case reporting in their jurisdictions.