Herpes simplex virus-2 may increase susceptibility of the sexual transmission of hepatitis C

OBJECTIVES: Antibodies against herpes simplex viruses-1 and -2, cytomegalovirus, and syphilis were determined in six heterosexual couples with strong indications of having sexually transmitted hepatitis C virus infection and in 17 other heterosexual couples in which one partner was hepatitis C virus viremic (source partner), but the other had remained hepatitis C virus uninfected (exposed partner). STUDY DESIGN. Antibody testing was done with an enzyme-linked immunosorbent assay. Anti-herpes simplex virus 2 and anti-hepatitis C virus findings were further confirmed by immunoblotting. Hepatitis C virus RNA was determined by polymerase chain reaction and genotyped with type-specific primers. RESULTS. Five of six anti-hepatitis C virus-positive exposed heterosexual partners without parenteral risk factors, compared with three of 17 anti-hepatitis C virus-negative exposed partners, had antibodies to herpes simplex virus-2. On the other hand, no statistically significant difference was found regarding the frequency of herpes simplex virus-2 seropositivity when source partners in the anti-hepatitis C virus concordant and discordant couples were compared. The presence of antibodies to herpes simplex virus-1, cytomegalovirus, and syphilis did not significantly differ between source or exposed partners in anti-hepatitis C virus concordant and discordant couples, respectively. No predominance of any one hepatitis C virus genotype or liver morphology in couples concordant compared with discordant for anti-hepatitis C virus was found. CONCLUSIONS. The findings support the role of herpes simplex virus-2 in the heterosexual transmission of hepatitis C virus infections, and more specifically an increase in susceptibility to hepatitis C virus infections in exposed heterosexual partners with antibodies to herpes simplex virus-2

Genotyping of hepatitis C virus isolates by a modified polymerase chain reaction assay using type specific primers: epidemiological applications

A polymerase chain reaction (PCR)-based assay using primers against the hepatitis C core gene has been described [Okamoto et al. (1992a): Journal of General Virology 73:673-679]. Within the two major HCV genotypes 1 and 2, the Okamoto system identifies two subtypes each (1a, 1b and 2a, 2b, respectively). Typing is achieved by a primary PCR with consensus primers followed by a nested PCR with type specific primers. The original assay was modified by addition of a parallel second PCR identifying the recently described major genotype 3. The assay also identifies in duplicate subtype 1b (type II by Okamoto), suggested to respond poorly to interferon. Reaction conditions were reviewed and melting temperatures of all typing primers equalised to increase strigency. The modified system functioned well and typing results were supported by partial core sequencing. The following distribution of genotypes was found in 53 hepatitis C virus (HCV) infected Swedish blood donors: genotype 1a (57%), 3 (19%), 1b (13%), and 2b (11%). In six recipients of HCV infected blood identified in a retrospective study, the recipient HCV genotype was identical to donor HCV genotype. Furthermore, in HCV positive couples identical genotype was observed when only one partner had an external risk factor; whereas genotypes were often diverse if both sex partners had parenteral risk factors. Finally, a cluster of hepatitis C cases in a haemodialysis unit was evaluated retrospectively. Eight patients had genotype 1b, two had mixed 1a and 1b, and one had type 1a. The modified HCV genotyping assay was of value in examining different epidemiological situations and can be expanded presumably to include future genotypes