Characterization of a hepatitis a outbreak in underserved urban tertiary safety net hospitals

Outbreaks of Hepatitis A, caused by the Hepatitis A Virus (HAV), remain a worldwide health concern. We conducted a retrospective chart review to characterize patients with acute HAV during an outbreak at our urban tertiary care center to better characterize patients infected with HAV. We searched our electronic records for patients with positive HAV IgM antibodies during a period of outbreak in Philadelphia, May 2017-December 2019. Characteristics of patients were recorded. We searched an equal period of time prior to the outbreak, September 2014-April 2017, to compare the two patient populations. During the outbreak we diagnosed 205 cases of acute HAV compared to just 23 during an equal time period prior to the onset of the outbreak. When compared to the results reported by the public health department for 2019, this accounted for 39.9% of patients documented in the city. A history of drug use was found in 49.4% of our patients while 19.5% of patients were homeless. Our analysis of homelessness and drug usage among documented cases of HAV during the outbreak period mirrored data reported by the city. Further, our analysis found that 7 zip codes accounted for 60% of our patients. Biochemical measures of liver function were higher in patients examined during the outbreak.