First report of a human autochthonous hepatitis E virus infection in Brazil

Abstract

Background Sporadic acute hepatitis E cases occurring in non-endemic areas have been associated to genotypes 3 and 4 of hepatitis E virus. Several studies have demonstrated the relationship among human and animals strains, mostly pigs and deers, from respective areas characterizing zoonosis. Circulation of genotype 3 of HEV in Brazilian swine herds have already been demonstrated. Nevertheless, no confirmed human cases have been reported to date in Brazil. Objectives A study was developed to attempt the identification of hepatitis E acute cases in Brazil. Study design A retrospective study carried out with 64 serum samples from patients with acute non-A–C hepatitis was performed to identify human cases of acute hepatitis E. Results We could identify a confirmed case of acute hepatitis E. The patient seroconverted to hepatitis E virus-specific IgM and IgG antibody, HEV-RNA was amplified from serum, and the analysis of the sequence of a 242 nucleotide fragment from the ORF1 genome region classified the strain within genotype 3 and subgenotype 3b. Investigation of risk factors and results from phylogenetic analysis suggested a likely zoonotic origin for the infection. Conclusions The first report of a human autochthonous in Brazil contributes with new information for hepatitis E epidemiology in Latin America and to considerate further broadly epidemiological studies.