Background
Geographic
and sociodemographic characterization of hepatitis C virus (HCV) transmission
amongst men who have sex with men (MSM) has been limited. Our aim was to
characterize HCV prevalence, risk factors for HCV co-infection, and patterns of
HIV and HCV co-transmission and transmitted drug resistance mutations (DRMs) in
newly HIV-diagnosed Los Angeles MSM.
Methods
Viral
RNA was extracted from stored plasma samples from a Los Angeles cohort of newly
diagnosed HIV-infected MSM with well-characterized substance use and sexual
behavioral characteristics via computer-assisted self-interviewing surveys.
Samples were screened for HCV by qPCR. HCV E1, E2, core, NS3 protease and NS5B
polymerase and HIV-1 protease and reverse transcriptase regions were amplified
and sequenced. Phylogenetic analysis was used to determine relatedness of HCV
and HIV-1 isolates within the cohort and viral sequences were examined for
DRMs.
Results
Of
185 newly HIV-diagnosed MSM, the majority (65 %) were of minority
race/ethnicity and recently infected (57.8 %), with median age of
28.3 years. A minority (6.6 %) reported injection drug use (IDU),
whereas 96 (52.8 %) reported recent substance use, primarily cannabis or
stimulant use. High risk sexual behaviors included 132 (74.6 %) with
unprotected receptive anal intercourse, 60 (33.3 %) with group sex, and 10
(5.7 %) with fisting. Forty-five (24.3 %) had acute gonorrhea or
chlamydia infection. Only 3 (1.6 %) subjects had detectable HCV RNA.
Amongst these subjects, HIV and HCV isolates were unrelated by phylogenetic
analysis and none possessed clinically relevant NS3 or NS5B HCV DRMs.
Conclusions
Prevalence
of HCV co-infection was low and there was no evidence of HIV-HCV
co-transmission in this cohort of relatively young, predominantly minority,
newly HIV-diagnosed MSM, most with early HIV infection, with high rates of high
risk sexual behaviors, STI, and non-IDU. The low HCV prevalence in a group with
high-risk behaviors for non-IDU HCV acquisition suggests an opportune time for
targeted HCV prevention measures.
Below: a Phylogenetic analysis of Hepatitis C virus (HCV)
isolates. Consensus sequences of an 857 nucleotide (nt) fragment of the HCV NS3
protease from the three HCV isolates from the cohort were aligned with the Los
Alamos National Laboratory HCV Database consensus sequences for HCV genotype
(gt) 1a and 3a, along with additional reference sequences from subjects living
in Los Angeles, to make a neighbor-joining tree. The consensus sequences for gt
1a and 3a are labeled as “CON” with the corresponding genotype. The Los Angeles
HCV sequences are labeled as “LA” with the corresponding subject number. The
HCV-positive subject samples are labeled A, B, and C. The tree is rooted with
the HCV genotype 1a consensus sequence and the genetic distance scale bar is
located at the center of the figure. b Phylogenetic analysis of HIV-1 pol. A 1302 nt fragment of pol covering
the HIV-1 protease and reverse transcriptase (HXB2 reference location nt
2254–3555) from N = 148 isolates from the cohort was aligned with the
Clade B consensus and used to build a neighbor-joining tree. Each sequence is
labeled with a unique subject identifier, and the HCV-positive subjects are
labeled A, B, and C. The tree is rooted with the Clade B consensus sequence.
The genetic distance scale bar is located at the lower left of the figure

By: Kara
W. Chew1*, Martha L. Blum23, Marjan Javanbakht4, Laurel E. Clare2, Lorelei D. Bornfleth2, Robert Bolan5, Debika Bhattacharya2 and Pamina M. Gorbach46
1Department of Medicine, David Geffen School
of Medicine at UCLA, 11075 Santa Monica Blvd, Suite 100, Los Angeles 90025, CA,
USA
2Department of Medicine, David Geffen School
of Medicine at UCLA, 10833 Le Conte Ave, 37-121 CHS, Los Angeles 90095, CA, USA
3Present Address: Community Hospital of the
Monterey Peninsula, Infectious Diseases Division, 23625 Holman Highway,
Monterey 93942, CA, USA
4Department of Epidemiology, UCLA Fielding
School of Public Health, 71-235E CHS, Los Angeles 90095, CA, USA
5Los Angeles LGBT Center, 1625 N. Schrader
Blvd, Los Angeles 90028, CA, USA
6Department of Medicine, David Geffen School
of Medicine at UCLA, 41-295 CHS, Los Angeles 90095, CA, USA