New hepatitis viruses

RESUMO

Three new hepatitis viruses are reviewed; Hepatitis EVirus (HEV), Hepatitis G Virus (HGV), and Transfusion Transmited Virus (TTV). Only HEV has been clearly associated with liver damage. It is transmited by the fecal-oral route and tends to occur in poor socio-economic conditions. Acute disease is diagnosed by the presence of anti-HEV IgM antibodies in the serum. Hepatitis G virus and TTV are transmitted parenterally. HGV is the same agent as GBV-C. Although it is hepatotropic, and high levels of viremia may occur, pathogenicity to the liver has not been proven, TTV may also be transmitted by the fecal-oral route. It is abundant in liver tissue but, like HGV, pathogenicity has not been proven.