Genetic characteristics and pathogenicity of human hepatitis E virus in Nanjing, China.

AIM: To investigate the genetic characteristics and pathogenicity of hepatitis E virus (HEV) and assess the potential risk factors for sporadic hepatitis E. METHODS: Sixty-two serum samples from the patients with acute hepatitis E were collected, including 23 cases coinfected with hepatitis B virus. Anti-HEV detection and partial HEV RNA amplification were performed by enzyme immunoassays and reverse transcription-nested polymerase chain reaction (RT-nPCR) method, respectively, and PCR products were sequenced. The isolated human HEV sequences were analyzed phylogenetically. RESULTS: The positive rate of serum HEV RNA were 21.0% (13/62), including 5 cases of liver failure. All the 13 isolates shared a 82.1%-98.0% nucleotide homology with each other and had identities of 74.7%-81.0%, 75.3%-78.6%, 75.3%-80.0% and 82.1%-96.1% with the corresponding regions of HEV genotypes 1-4, respectively. The human HEV strain GS-NJ-12 shared a 100% nucleotide identity with the swine HEV strain swIM6-43 isolated from Inner Mongolia, China. CONCLUSION: Swine may be a principal risk factor for occurrence of sporadic hepatitis E in eastern China, and genotype 4 HEV can induce acute liver failure.