Hepatitis G virus

Hepatitis G virus (HGV) , formerly known as GB virus C (GBV-C), is a virus in the Flaviviridae family which has not yet been assigned to a genus. It is known to infect humans, but is not known to cause human disease. There have been reports that HIV patients coinfected with GBV-C can survive longer than those without GBV-C, but the patients may be different in other ways. There is current active research into the virus effects on the immune system in patients coinfected with GBV-C and HIV
Taxonomy:
HGV is a member of the Flaviviridae family and is phylogenetically related to HCV but appears to replicate primarily in lymphocytes, and poorly in hepatocytes. GBV-A and GBV-B are probably tamarin viruses, while GBV-C infects humans
Human infection:
The majority of immune-competent individuals appear to clear GBV-C viraemia within the first few years following infection and although the time interval between GBV-C infection and clearance of viraemia (detection of GBV-C RNA in plasma) is not known, infection may persist for decades in some individuals.
Approximately, 2% of healthy blood donors are viraemic with GBV-C, and up to 13% of blood donors have antibodies to E2 protein, indicating prior infection
Some studies have suggested that co-infection with GBV-C will actually slow the progression of HIV disease.
Transmission:
Parenteral, sexual and vertical transmission of GBV-C have all been documented, and because of shared modes of transmission, individuals infected with HIV are commonly co-infected with GBV-C. Among people with HIV infection, the prevalence of GBV-C viraemia ranges from 14 to 43%