title: A multicentre sero-behavioural survey for hepatitis B and C, HIV and HTLV among people who inject drugs in Germany using respondent driven sampling.
abstract: BACKGROUND
  People who inject drugs are at high risk for hepatitis B, hepatitis C and HIV. HTLV was reported by neighboring countries to be prevalent in this population, but the situation for Germany is unclear. To generate seroprevalence and related behavioural data and to enhance prevention efforts against these infections for drug users in Germany, a multicentre sero- and behavioural survey was initiated. People who inject drugs are not well reached by services for testing and counselling for blood-borne infections in Germany. An interventional part of the study is intended to prove feasibility and acceptance of testing and counselling in low-threshold drop-in settings.
  
  
  METHODS
  Between May 2011 and March 2015, eligible participants (persons having injected drugs within the last 12 months, aged 16 years+, and living in the study city) are recruited by respondent driven sampling, using low-threshold drop-in facilities as study-sites in eight German cities with large drug scenes. Calculated sample size is 2,033 participants. Capillary blood samples collected as dried blood spots are anonymously tested for serological and molecular markers of hepatitis B and C, HIV, and HTLV I and II. A detailed face-to-face-interview about hepatitis- and HIV-related knowledge, former testing, imprisonment, sexual and injecting risk behaviour is conducted with participants. Staff is trained to offer pre- and post-test-counselling of blood-borne infections and HIV rapid testing to participants.
  
  
  CONCLUSIONS
  We chose respondent driven sampling for recruitment of participants to improve representativeness of results. Persons, who are not reached by the facility where the study is conducted, are aimed to be included by recruitment through their personal social network of injecting drug users. To reduce differential biases in the questions on knowledge of transmission and prevention of infections, we present true statements on hepatitis B, C and HIV, their possible routes of transmission and measures of prevention to participants. Participants are told that the statements are true and are asked to answer if they knew this fact already or if it is new to them. In case of knowledge gaps they are offered free targeted counselling as well as free HIV rapid testing and post-test counselling of HIV and hepatitis test results.
authors.affiliation: Department for Infectious Disease Epidemiology, Division for HIV/AIDS, STI and Blood-borne Infections, Robert Koch Institute, Berlin, Germany. ZimmermannR@rki.de.
authors.forename: Ruth
authors.initials: R
authors.lastname: Zimmermann
authors.forename: Ulrich
authors.initials: U
authors.lastname: Marcus
authors.forename: Dirk
authors.initials: D
authors.lastname: Schäffer
authors.forename: Astrid
authors.initials: A
authors.lastname: Leicht
authors.forename: Benjamin
authors.initials: B
authors.lastname: Wenz
authors.forename: Stine
authors.initials: S
authors.lastname: Nielsen
authors.forename: Claudia
authors.initials: C
authors.lastname: Santos-Hövener
authors.forename: R Stefan
authors.initials: RS
authors.lastname: Ross
authors.forename: Oumaima
authors.initials: O
authors.lastname: Stambouli
authors.forename: Boris-Alexander
authors.initials: BA
authors.lastname: Ratsch
authors.forename: Norbert
authors.initials: N
authors.lastname: Bannert
authors.forename: Claus-Thomas
authors.initials: CT
authors.lastname: Bock
authors.forename: Claudia
authors.initials: C
authors.lastname: Kücherer
authors.forename: Osamah
authors.initials: O
authors.lastname: Hamouda
mesh_terms: D000293:Adolescent; D000328:Adult; D003376:Counseling; D005260:Female; D005858:Germany / Q000453:epidemiology; D015658:HIV Infections / Q000453:epidemiology / Q000517:prevention & control; D015490:HTLV-I Infections / Q000453:epidemiology / Q000517:prevention & control; D006306:Health Surveys; D006509:Hepatitis B / Q000453:epidemiology / Q000517:prevention & control; D006526:Hepatitis C / Q000453:epidemiology / Q000517:prevention & control; D006801:Humans; D008297:Male; D008403:Mass Screening / Q000379:methods; D012309:Risk-Taking; D016036:Seroepidemiologic Studies; D015819:Substance Abuse, Intravenous / Q000453:epidemiology*