title: HCV prevalence and risk behaviours among injectors of new psychoactive substances in a risk environment in Hungary-An expanding public health burden.
abstract: In Hungary a large increase in injecting new psychoactive substances (NPS) coincided with decreasing harm reduction efforts and rising HCV infection. We describe these, and assess changes in HCV prevalence and risk behaviours, 2011-2014, among NPS injectors, using 2011-2015 syringe exchange programme (SEP) data as a key contextual ('risk environment') variable.
  
  
  
  We conducted repeated national sero-behavioural surveys in people who inject drugs (PWID) injecting in the last month and attending SEPs or drug treatment centres (n=399, 2011; 384, 2014), using face-to-face interviews and dried blood-spot samples. Prevalence of injected drugs and SEP coverage (2011-2015) were assessed through our national SEP monitoring system and using population size estimates.
  
  
  
  NPS injecting tripled among PWID attending SEPs in Hungary (2011: 26%; 2015: 80%). Among NPS injectors, HCV prevalence, sharing syringes and sharing any injecting equipment (last month), doubled (2011-2014: 37%-74%, 20%-48%, 42%-71%, respectively), significantly exceeding prevalence in other PWID groups. Among young NPS injectors (aged<25), HCV prevalence increased 7-fold (12%-76%), among new injectors (injecting<2years) 4-fold (13%-42%), coupled with high levels of equipment sharing (79% and 72% respectively). Not using a condom at last intercourse (79%), ever-imprisonment (65%) and last-year homelessness (57%) were highly prevalent among NPS injectors (2014). The number of syringes distributed per estimated PWID nationally fell from 114 to 81 (2011-2014) and dropped to 28 in 2015.
  
  
  
  NPS injectors in Hungary are at severe risk of blood-borne infections due to high levels of injecting and sexual risk behaviours within a high-risk environment, including continuously low SEP provision, imprisonment and homelessness. An HIV outbreak cannot be excluded. Stronger investment in evidence-based prevention measures, with special focus on young and new injectors, and expansion of hepatitis C treatment are urgently needed.
authors.affiliation: Hungarian Reitox National Focal Point, Albert Flórián út 2-6, Budapest 1097, Hungary; Semmelweis University, School of PhD Studies, Üllői u. 26, Budapest 1085, Hungary. Electronic address: tarjan.anna@gmail.com.
authors.forename: Anna
authors.initials: A
authors.lastname: Tarján
authors.affiliation: Department for Communicable Diseases, National Centre for Epidemiology, Albert Flórián út 2-6, Budapest 1097, Hungary.
authors.forename: Mária
authors.initials: M
authors.lastname: Dudás
authors.affiliation: European Monitoring Centre for Drugs and Drug Addiction, Praça Europa 1, Cais do Sodré, Lisbon 1249-289, Portugal.
authors.forename: Lucas
authors.initials: L
authors.lastname: Wiessing
authors.affiliation: Hungarian Reitox National Focal Point, Albert Flórián út 2-6, Budapest 1097, Hungary; Semmelweis University, School of PhD Studies, Üllői u. 26, Budapest 1085, Hungary.
authors.forename: Gergely
authors.initials: G
authors.lastname: Horváth
authors.affiliation: Division of Virology, National Centre for Epidemiology, Albert Flórián út 2-6, Budapest 1097, Hungary.
authors.forename: Erzsébet
authors.initials: E
authors.lastname: Rusvai
authors.affiliation: Division of Virology, National Centre for Epidemiology, Albert Flórián út 2-6, Budapest 1097, Hungary.
authors.forename: Bálint
authors.initials: B
authors.lastname: Tresó
authors.affiliation: Department for Communicable Diseases, National Centre for Epidemiology, Albert Flórián út 2-6, Budapest 1097, Hungary.
authors.forename: Ágnes
authors.initials: Á
authors.lastname: Csohán
mesh_terms: D059788:Dried Blood Spot Testing; D040261:Harm Reduction; D006526:Hepatitis C / Q000453:epidemiology*; D006703:Ill-Housed Persons / Q000706:statistics & numerical data; D006801:Humans; D006814:Hungary / Q000453:epidemiology; D007407:Interviews as Topic; D016485:Needle Sharing / Q000706:statistics & numerical data; D018671:Needle-Exchange Programs; D015995:Prevalence; D011329:Prisoners / Q000706:statistics & numerical data; D011619:Psychotropic Drugs / Q000008:administration & dosage* / Q000009:adverse effects; D011634:Public Health; D012309:Risk-Taking; D012725:Sexual Behavior / Q000706:statistics & numerical data; D015819:Substance Abuse, Intravenous / Q000150:complications / Q000453:epidemiology*; D011795:Surveys and Questionnaires; D047568:Unsafe Sex / Q000706:statistics & numerical data
chemical_list: D011619:Psychotropic Drugs
keywords: HIV; Harm reduction; Hepatitis C; Injecting drug use; New psychoactive substances; Risk behaviours