Hepatitis A surveillance using commercial laboratory data

ObjectiveTo evaluate the use of commercial laboratory data for monitoring trends in HAV infections over time and identifying geographic and demographic characteristics of HAV case clusters for the purpose of targeting interventions.IntroductionHepatitis A virus (HAV) infections have persisted in the United States despite the availability of an effective vaccine. Recent outbreaks of HAV infections among unvaccinated adults attributed to consumption of HAV-contaminated food, or person-to-person contact in certain populations (e.g., men who have sex with men) or settings (e.g., homeless shelters) have emphasized the importance of targeted vaccination of at-risk adults.MethodsWe used commercial laboratory data from Quest Diagnostics (Quest) and Laboratory Corporation of America (LabCorp) to identify unique individuals within each database who tested positive for HAV IgM antibody (indicative of acute HAV infection) from January 2011 through June 2017. Though de-depulication across the two laboratories was not possible, comparison of case characteristics indicated limited possible overlap of cases (