title: HCV reinfection incidence among individuals treated for recent infection.
abstract: One challenge to HCV elimination through therapeutic intervention is reinfection. The aim of this analysis was to calculate the incidence of HCV reinfection among both HIV-positive and HIV-negative individuals treated for recent HCV infection (estimated infection duration <18 months). Individuals with recent HCV infection who achieved an end-of-treatment response in four open-label studies between 2004 and 2015 in Australia and New Zealand were assessed for HCV reinfection, confirmed by sequencing of the Core-E2 and/or NS5B regions. Reinfection incidence was calculated using person-time of observation. Exact Poisson regression analysis was used to assess factors associated with HCV reinfection. The cohort at risk for reinfection (n=120; 83% male; median age 36 years) was composed of HIV-positive men-who-have-sex-with-men (53%) and people who inject drugs (current 49%, ever 69%). Total follow-up time at risk was 135 person-years (median 1.08 years, range 0.17, 2.53). Ten cases of HCV reinfection were identified, for an incidence of 7.4 per 100 py (95% CI 4.0, 13.8). Reinfection incidence was significantly higher among participants who reported injection drug use at end of or post-treatment, irrespective of HIV status (15.5 per 100 py, 95% CI 7.8, 31.1). In adjusted analysis, factors associated with reinfection were older age (aIRR 5.3, 95% CI 1.15, 51.5, P=.042) and injection drug use at end of or post-treatment (aIRR 7.9, 95% CI 1.6, 77.2, P=.008). High reinfection incidence following treatment for recent HCV infection in individuals with ongoing risk behaviour emphasizes the need for post-treatment surveillance, harm reduction strategies and education in at-risk populations.
authors.affiliation: Viral Hepatitis Clinical Research Program, Kirby Institute, UNSW Australia, Sydney, NSW, Australia.
authors.forename: M
authors.initials: M
authors.lastname: Martinello
authors.affiliation: Viral Hepatitis Clinical Research Program, Kirby Institute, UNSW Australia, Sydney, NSW, Australia.
authors.forename: J
authors.initials: J
authors.lastname: Grebely
authors.affiliation: Viral Hepatitis Clinical Research Program, Kirby Institute, UNSW Australia, Sydney, NSW, Australia.
authors.forename: K
authors.initials: K
authors.lastname: Petoumenos
authors.affiliation: Auckland Hospital, Auckland, New Zealand.
authors.forename: E
authors.initials: E
authors.lastname: Gane
authors.affiliation: Centre for Population Health, Burnet Institute, Melbourne, Vic., Australia.|Infectious Diseases Unit, Alfred Hospital, Melbourne, Vic., Australia.|Department of Epidemiology and Preventative Medicine, Monash University, Melbourne, Vic., Australia.
authors.forename: M
authors.initials: M
authors.lastname: Hellard
authors.affiliation: Infectious Diseases Unit, Royal Adelaide Hospital, Adelaide, SA, Australia.
authors.forename: D
authors.initials: D
authors.lastname: Shaw
authors.affiliation: Victorian Infectious Diseases Service, Royal Melbourne Hospital, Melbourne, Vic., Australia.
authors.forename: J
authors.initials: J
authors.lastname: Sasadeusz
authors.affiliation: Viral Hepatitis Clinical Research Program, Kirby Institute, UNSW Australia, Sydney, NSW, Australia.
authors.forename: T L
authors.initials: TL
authors.lastname: Applegate
authors.affiliation: Viral Hepatitis Clinical Research Program, Kirby Institute, UNSW Australia, Sydney, NSW, Australia.|Department of Infectious Disease and Immunology, St Vincent's Hospital, Sydney, NSW, Australia.
authors.forename: G J
authors.initials: GJ
authors.lastname: Dore
authors.affiliation: Viral Hepatitis Clinical Research Program, Kirby Institute, UNSW Australia, Sydney, NSW, Australia.|Department of Infectious Disease and Immunology, St Vincent's Hospital, Sydney, NSW, Australia.
authors.forename: G V
authors.initials: GV
authors.lastname: Matthews
mesh_terms: D000328:Adult; D044966:Anti-Retroviral Agents / Q000627:therapeutic use*; D001315:Australia / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D005838:Genotype; D060005:Genotyping Techniques; D016174:Hepacivirus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification; D006526:Hepatitis C / Q000188:drug therapy* / Q000453:epidemiology*; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009520:New Zealand / Q000453:epidemiology; D010802:Phylogeny; D012008:Recurrence; D012307:Risk Factors; D012309:Risk-Taking; D017422:Sequence Analysis, DNA; D014764:Viral Proteins / Q000235:genetics
chemical_list: D044966:Anti-Retroviral Agents; D014764:Viral Proteins
keywords: 
  HIV
  ; acute; hepatitis C infection; recent; reinfection; treatment