CROI 2016 Abstract eBook

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Oral Abstracts

149 Networks of HCV Transmissions Among Persons Who Inject Drugs: Indiana, 2015 Sumathi Ramachandran 1 ; EyasuTeshale 1 ;William Switzer 1 ; Philip Peters 1 ; Romeo R. Galang 1 ; Pamela Pontones 2 ; Jessica Gentry 2 ; Sara J. Blosser 2 ; JohnWard 1 ;Yury Khudyakov 1 ; for the HIV-HCVTransmission Investigation team 1 CDC, Atlanta, GA, USA; 2 Indiana State Dept of Hlth, Indianapolis, IN, USA Background: Early in 2015, an outbreak of HIV-1 infection associated with injection of the prescription opioid oxymorphone was identified in Scott County, Indiana. The investigation revealed that the affected community had a high prevalence of hepatitis C virus (HCV) infection. To characterize the circulating HCV strains, molecular anlaysis of HCV from 492 specimens was conducted. Methods: HCV strains were genotyped using phylogenetic analysis of NS5b sequences. To sample intra-host HCV variants (quasispecies), next generation sequencing (NGS) of the HCV hypervariable region 1 (HVR1) was performed. NGS HVR1 sequences were analyzed using Global Hepatitis Outbreak and Surveillance Technology (GHOST), a recently developed bioinformatics toolkit for inferring genetic relationships among HCV strains and graphically presenting HCV transmission networks. Results: Of the 492 HCV antibody reactive specimens, 334 (67.9%) were HCV-RNA positive, and the distribution of HCV genotypes included: 1a (69.8%), 1b (2.4%), 2b (5.1%), 3a (22.8%). Among the cases of HCV infection, 23%were co-infected with HIV. Phylogenetic analysis of the NS5b sequences identified one major cluster of genotype 1a strains (n=104) with >93% homology, and 2 clusters of the genotype 3a strains (n=46; n=8) with >94% and 95% homology, respectively. Of the 240 cases tested by GHOST, 70 (29%) were infected with >1 HCV strain, and 46 (19%) were infected with >1 HCV genotype. One person was infected with 5 strains of genotypes 1a, 1b, 3 and 6. NGS analyses identified a total of about 335 HCV strains, with 65% of the strains organized into 19 transmission clusters (median cluster size = 3). One major transmission cluster involved 92 cases (Fig.1: Orange nodes). Fig.1: Network of transmission clusters identified by Global Hepatitis Outbreak and Surveillance Technology (GHOST). Clusters are color-coded; each node represents a case; size is proportional to HCV HVR1 heterogeneity. Links join cases with genetic distance below the relatedness threshold. Conclusions: Co-circulation of a large number of HCV strains indicates multiple independent introductions of HCV to the community over a long period of time. Identification of a third of the tested cases infected with >1 HCV strain highlights longstanding endemicity of HCV infection in the community. A complex transmission network genetically detected by GHOST reveals continuous HCV dissemination, and provides a novel tool to supplement public health intervention efforts for identification and disruption o

Oral Abstracts

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CROI 2016