An outbreak of hepatitis E in Yavatmal, India, 2019

Abstract

Hepatitis E, a public health concern in developing countries, frequently presents in epidemic, as well as in sporadic forms. This study investigated an outbreak of viral hepatitis at Yavatmal, Maharashtra, India in March 2019. Blood samples from 10 patients were received at Indian Council of Medical Research-National Institute of Virology, Pune to test for the presence of enterically transmitted hepatitis viruses. Subsequently, 49 suspected cases were screened for anti-hepatitis E virus (HEV)/hepatitis A virus (HAV) immunoglobulin M and immunoglobulin G (IgG) antibodies, alanine amino-transferase levels and HEV RNA. Water samples were screened for HEV and HAV RNA followed by phylogenetic analysis. Overall 32 of 49 (65.3%) suspected cases had recent acute HEV infection, while dual infection with HAV was noted in one case (2.04%). Forty-eight of 49 suspected cases were positive for anti-HAV IgG antibodies indicative of previously acquired immunity against HAV. Water samples had evidence of HEV contamination as detected by reverse transcription-polymerase chain reaction. Sequencing of HEV RNA from both patients (n = 2) and water samples (n = 5) indicated HEV genotype 1 to be the etiological agent of this outbreak. Serological and molecular evidence confirmed HEV as the etiology. Mixing of contaminated drain water with the domestic water supply may have triggered this outbreak. Subsequent changing of the defaulted water pipelines and its segregation from drain pipelines by the health authorities resulted in progressive decline of this outbreak. Despite the limitations, periodic surveillance of HEV exposure pattern and reporting of small outbreaks would supplement to the global disease burden data of hepatitis E.

Keywords: India; Yavatmal; drainage water; hepatitis E outbreak.