Seroepidemiology of a recent outbreak of Hepatitis E in urban Shimla, Himachal Pradesh, India

Hepatitis E, a major public health problem, continues to cause epidemics in different geographic areas in India and poses multi-sectoral challenges. The aim of the study was to determine the seroepidemiology of the hepatitis outbreak in the urban areas of district Shimla, Himachal Pradesh. Patients presenting with clinical features of acute viral hepatitis during and after the epidemic period were tested for seromarkers; IgM anti-HEV and IgM anti-HAV by enzyme linked immunosorbant assay. The weekly reporting under Integrated Disease and Surveillance Programme (IDSP) for cases of jaundice from Shimla from December 2015 to April 2016 was reviewed. The outbreak of hepatitis due to contamination of drinking water supply in urban Shimla beginning December 12, 2015 was confirmed by IDSP. A total of 425 serum samples (males: 292; females: 133) were tested for IgM anti-HAV and IgM anti-HEV by ELISA. Liver enzymes where deranged in all cases. Serological evidence of infection with HAV and/or HEV was seen in 64%. HEV infection alone was detected in 62.13%. All ages were affected, with one case of HEV infection below ten years. HEV infection alone was 5 times more common than HAV infection and co-infection was detected in 69 cases (m: 47; f:22). Six antenatal mothers were anti-HEV positive and the maternal mortality of 50% (n=3) due to fulminant hepatitis. Since HAV and HEV have a similar faecal-oral route of transmission, this study highlights periodic surveillance of HAV/HEV exposure pattern to improve levels of personal and food hygiene and inter-sectoral collaboration for provision of safe water supply and safe sewage disposal.