Assessing routes of hepatitis C transmission in HIV-infected men who have sex with men using single genome sequencing.

The epidemic of hepatitis C virus (HCV) infection among HIV-infected men who have sex with men (MSM) is in its second decade, but the routes of transmission remain poorly understood. We hypothesized that by pairing single genome sequencing (SGS), to enumerate infecting HCV genomes (viruses), with detailed sexual and drug histories, we could gain insight into the routes of transmission among MSM. We used SGS to analyze blood specimens from eight HIV-infected MSM who had 10 episodes of acute (seronegative) or early HCV infections. Seven of eight men reported condomless receptive anal intercourse (CRAI), six with rectal exposure to semen, and all eight denied rectal trauma or bleeding. Of the 10 HCV infections, eight resulted from transmission of a single virus; one infection resulted from transmission of either one or a few (three or four) closely-related viruses; and one infection resulted from transmission of >10 distinct viruses. The participant infected by >10 viruses reported sharing injection equipment for methamphetamine during sex. Two other participants also injected methamphetamine during sex but they did not share injection equipment and were infected by a single virus. Conclusions: Most HCV infections of HIV-infected MSM without a history of either rectal trauma or bleeding or shared injection equipment were caused by a single virus. Intra-rectal exposure to semen during CRAI is therefore likely sufficient for HCV transmission among MSM. Conversely, rectal trauma or bleeding or shared injection equipment are not necessary for HCV transmission among MSM. These results help clarify routes of HCV transmission among MSM and can therefore help guide the design of much-needed behavioral and other interventions to prevent HCV transmission among MSM.

Déclaration de conflit d'intérêts

I have read the journal's policy and the following authors of this manuscript have the following competing interests: Kristen M. Marks: reports research funding paid to her institution outside the submitted work from Gilead Sciences, Merck, and Bristol-Myers Squibb Andrew H. Talal: reports having served as a speaker, a consultant, and an advisory board member for Abbott Laboratories, and has received research funding from Merck Inc, Gilead, Abbott Laboratories, AbbVie, Intercept, Conatus, and Bristol-Myers-Squibb. Bisher Akil: reports receiving contract, consultant, and speaker fees from ViiV Healthcare Andrea D. Branch: reports having served as a consultant to Boehringer Ingelheim and receiving research funding paid to her institution from Gilead Sciences Daniel S. Fierer: reports research funding paid to his institution outside the submitted work from Gilead Sciences and Merck. The following authors have declared that no competing interests exist: Hui Li; Wouter O. van Seggelen; Asa Radix; Shirish Huprikar; Shuyi Wang; George M. Shaw. This does not alter our adherence to PLOS ONE policies on sharing data and materials.