title: Transmission dynamics of hepatitis C virus among intra venous drug users in the border state of Manipur, India.
abstract: Intra venous drug users (IVDUs) are at high risk for hepatitis C virus (HCV) infection owing to their high rate of drug abuses. The north-eastern part of India has a high prevalence of IVDUs with Manipur being the worst hit state. The aim of the study was to document the molecular epidemiology, the patterns of HCV transmission, genomic variation and recombination events within HCV genome among IVDUs of Manipur, India. 91 anti-HCV sero-reactive blood samples were collected from IVDUs in Manipur. The samples were processed for RNA extraction, nested RT-PCR, sequencing and quantitative viral RNA estimation. Phylogeographic analysis of the sequenced core and NS5B regions of HCV genome was performed to determine the probable transmission route and recombinant HCV strains. 83 out of 91 anti-HCV seropositive samples were RNA positive (91.20%) based on 5'UTR of HCV genome by nested RT-PCR. Of the RNA positive samples, 73 paired partial core and NS5B gene were sequenced. Three major genotype and eight subtypes were detected while no recombinant strains were found. Individuals with genotype 1 had the mean viral load (5.94 ± 0.705 log10IU/ml) followed by genotype 3 (4.91 ± 0.49 log10IU/ml) and 6 (3.96 ± 0.32 log10IU/ml). The viral load was statistically significant among the male individuals at 4.822 ± 1.36 log10IU/ml compared to 4.767 ± 0.49 log10IU/ml for females (t=3.249, p<0.005). The phylogeographic results indicated 3b, 6h originated from Vietnam, 1a had Indian origin, 3a, 6k originated from southern China while 1b originated from Myanmar, respectively. The incidence of eight different subtypes in Manipur reflects the transmission of these strains from the "Golden Triangle" drug trafficking regions. Sequence analysis confirmed the transmission routes of HCV, which is linked to China and Vietnam for the newly emergent genotype 6 in north-eastern India.
authors.affiliation: ICMR Virus Unit, Kolkata, India.
authors.forename: Kallol
authors.initials: K
authors.lastname: Saha
authors.affiliation: ICMR Virus Unit, Kolkata, India.
authors.forename: Rushna
authors.initials: R
authors.lastname: Firdaus
authors.affiliation: ICMR Virus Unit, Kolkata, India.
authors.forename: Aritra
authors.initials: A
authors.lastname: Biswas
authors.affiliation: ICMR Virus Unit, Kolkata, India.
authors.forename: Anirban
authors.initials: A
authors.lastname: Mukherjee
authors.affiliation: National Institute of Cholera and Enteric Diseases, Kolkata, India.
authors.forename: Kamalesh
authors.initials: K
authors.lastname: Sarkar
authors.affiliation: ICMR Virus Unit, Kolkata, India.
authors.forename: Sekhar
authors.initials: S
authors.lastname: Chakrabarti
authors.affiliation: ICMR Virus Unit, Kolkata, India. Electronic address: provash2000@gmail.com.
authors.forename: Provash Chandra
authors.initials: PC
authors.lastname: Sadhukhan
mesh_terms: D001483:Base Sequence; D015331:Cohort Studies; D064423:Drug Trafficking; D055030:Drug Users; D005260:Female; D014644:Genetic Variation; D016679:Genome, Viral / Q000235:genetics; D005838:Genotype; D016174:Hepacivirus / Q000145:classification / Q000235:genetics* / Q000472:pathogenicity; D006526:Hepatitis C / Q000453:epidemiology / Q000635:transmission*; D018937:Hepatitis C Antibodies / Q000097:blood; D006801:Humans; D007194:India / Q000453:epidemiology; D008297:Male; D017720:Molecular Epidemiology; D058974:Phylogeography; D011446:Prospective Studies; D012367:RNA, Viral / Q000097:blood / Q000235:genetics; D017423:Sequence Analysis, RNA; D015819:Substance Abuse, Intravenous; D014758:Viral Core Proteins / Q000235:genetics; D019562:Viral Load; D017361:Viral Nonstructural Proteins / Q000235:genetics*; D012324:RNA-Dependent RNA Polymerase
chemical_list: D018937:Hepatitis C Antibodies; D012367:RNA, Viral; D014758:Viral Core Proteins; D017361:Viral Nonstructural Proteins; C087036:NS-5 protein, hepatitis C virus; D012324:RNA-Dependent RNA Polymerase
keywords: Drug trafficking; Intra venous drug users; Phylogeographic analysis; Recombinant HCV; Transmission risk reduction