ICTV Virus Taxonomy Profile: Hepeviridae 2022

Abstract

The family Hepeviridae includes enterically transmitted small quasi-enveloped or non-enveloped positive-sense single-stranded RNA viruses infecting mammals and birds (subfamily Orthohepevirinae) or fish (Parahepevirinae). Hepatitis E virus (genus Paslahepevirus) is responsible for self-limiting acute hepatitis in humans; the infection may become chronic in immunocompromised individuals and extrahepatic manifestations have been described. Avian hepatitis E virus (genus Avihepevirus) causes hepatitis-splenomegaly syndrome in chickens. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family Hepeviridae, which is available at www.ictv.global/report/hepeviridae.

Keywords: Hepeviridae; ICTV report; hepatitis E virus; taxonomy.

Fig. 1.. (a) Negative-contrast electron micrograph of human hepatitis E virus particles from a case stool collected in Nepal. (V) virion and (E) empty capsid. Bar: 100 nm (photograph M. Purdy). (b) Phylogeny of orthohepevirin methyltransferase domains (details: ICTV Report).

Fig. 2.. Genome organization of hepeviruses. There are short 5′- and 3′-non-coding regions. The ORF1 polyprotein includes the putative functional domains: MT, methyltransferase; P, a putative papain-like cysteine protease; HUD, hepevirus unique (or Z-) domain; PP, a hypervariable polyproline region; Macro, macro domain; Hel, helicase; and RdRP, RNA-directed RNA polymerase. ORF2 encodes the capsid protein (CP) and ORF3 a small phosphoprotein.