Clustering of HCV coinfections on HIV phylogeny indicates domestic and sexual transmission of HCV

Publication

Clustering of HCV coinfections on HIV phylogeny indicates domestic and sexual transmission of HCV

Journal Paper/Review - Jan 22, 2014

Kouyos Roger D, Günthard Huldrych F, Ledergerber Bruno, Bernasconi Enos, Vernazza Pietro, Battegay Manuel, Cavassini Matthias, Calmy Alexandra, Kovari Helen, Klimkait Thomas, Aubert Vincent, Shah Cyril, Yerly Sabine, Böni Jürg, Rauch Andri, Swiss HIV Cohort Study (SHCS)

Citation

Kouyos R, Günthard H, Ledergerber B, Bernasconi E, Vernazza P, Battegay M, Cavassini M, Calmy A, Kovari H, Klimkait T, Aubert V, Shah C, Yerly S, Böni J, Rauch A, Swiss HIV Cohort Study (SHCS). Clustering of HCV coinfections on HIV phylogeny indicates domestic and sexual transmission of HCV. Int J Epidemiol 2014; 43:887-96.

Type

Journal Paper/Review (English)

Journal

Int J Epidemiol 2014; 43

Publication Date

Jan 22, 2014

Issn Electronic

1464-3685

Pages

887-96

Brief description/objective

BACKGROUND
HCV coinfection remains a major cause of morbidity and mortality among HIV-infected individuals and its incidence has increased dramatically in HIV-infected men who have sex with men(MSM).

METHODS
Hepatitis C virus (HCV) coinfection in the Swiss HIV Cohort Study(SHCS) was studied by combining clinical data with HIV-1 pol-sequences from the SHCS Drug Resistance Database(DRDB). We inferred maximum-likelihood phylogenetic trees, determined Swiss HIV-transmission pairs as monophyletic patient pairs, and then considered the distribution of HCV on those pairs.

RESULTS
Among the 9748 patients in the SHCS-DRDB with known HCV status, 2768(28%) were HCV-positive. Focusing on subtype B(7644 patients), we identified 1555 potential HIV-1 transmission pairs. There, we found that, even after controlling for transmission group, calendar year, age and sex, the odds for an HCV coinfection were increased by an odds ratio (OR) of 3.2 [95% confidence interval (CI) 2.2, 4.7) if a patient clustered with another HCV-positive case. This strong association persisted if transmission groups of intravenous drug users (IDUs), MSMs and heterosexuals (HETs) were considered separately(in all cases OR>2). Finally we found that HCV incidence was increased by a hazard ratio of 2.1 (1.1, 3.8) for individuals paired with an HCV-positive partner.

CONCLUSIONS
Patients whose HIV virus is closely related to the HIV virus of HIV/HCV-coinfected patients have a higher risk for carrying or acquiring HCV themselves. This indicates the occurrence of domestic and sexual HCV transmission and allows the identification of patients with a high HCV-infection risk.