GB virus C

GB viruses are enveloped single-stranded RNA viruses with positive polarity. They are now in three different species (A, B, C ) is divided, which differ in their host and their pathogenicity. They are assigned to the Flaviviridae family provisionally. The name GB derives from the initials of the first patient in the 1996 virus isolation succeeded. At that time, the isolation in humans was falsely implicated in a hepatitis, where still referring to hepatitis G virus ( HGV) is due. Since it was discovered in monkeys very similar viruses ( GBV- A and GBV -B), the human variant is referred to as GB virus C ( GBV -C).

GB virus A

The GBV -A was found in six species of New World monkeys. They do not cause hepatitis, even with infection of non-naturally infected primates. The GBV- A can be experimentally transmitted by blood, however, the natural pathway is not known. In the genome of the GBV -A missing in comparison to the completely Hepaciviren the gene for a capsid protein.

GB virus B

The GB virus B ( GBV -B) is closely related to the hepatitis C virus (HCV ) related, but still clearly demarcated as a separate virus species. The GBV- B is assigned to the genus hepacivirus provisional. It was detected in New World monkeys and chimpanzees.

So far, only one isolate of GBV -B was found, which causes a brief, self-limited hepatitis in tamarins and owl monkeys.

GB virus C

In humans, the GBV- C occurs; it is like the GBV- A of the family Flaviviridae associated, but still no species. The GBV -C was erroneously regarded in 1996 as an independent agent of a so-called hepatitis G ( HGV). The 9.4 kb RNA genome has open reading frames ( open reading frame, ORF) coding for the envelope proteins E1 and E2 and for the non-structural proteins NS2, NS3, NS4A, NS4B, NS5A and NS5B.


The transmission of GB virus occurs through blood and blood products and possibly by contact infection or contact infection.

The infection with GBV- C in humans is somewhat more common in the absence of hepatitis C and is particularly common among drug addicts. In the normal population, however, about 60% of GBV- C, are already infected without any disease could be associated therewith. It is unclear what is the significance of this virus in humans, because it is considered unlikely that it causes an independent disease. Secure the infection is not associated with hepatitis, as originally believed. The only clinical effect has been shown is that people infected with HIV in which GBV- C is not detected, a higher HIV replication show as those in which the GBV -C is present. This suppressive effect of GBV -C on HIV is totally unclear in its mechanism.


For the detection of specific antibodies for a short time there was a commercial test, but this was taken after the refutation of an association with hepatitis from the market. The viral RNA of GBV -C can be detected in scientific issues in special laboratories.