title: Cross sectional study of factors associated to self-reported blood-borne infections among drug users.
abstract: BACKGROUND
  The study's aim was to estimate the self-reported prevalence of Human Immunodeficiency Virus (HIV) and Hepatitis C Virus (HCV), and to describe their associated risk factors in a population of users of illicit drugs recruited in Catalonia- Spain, during 2012.
  
  
  METHODS
  Cross-sectional study. People with illicit drugs use were selected in three different types of healthcare centres. The questionnaire was a piloted, structured ad hoc instrument. An analysis was made to identify factors associated to self-reported HCV, HIV and co-infection. Correlates of reported infections were determined using univariate and multivariate Poisson regression (with robust variance).
  
  
  RESULTS
  Among 512 participants, 39.65% self-reported positive serostatus for HCV and 14.84% for HIV, co-infection was reported by 13.48%. Among the 224 injecting drug users (IDUs), 187 (83.48%), 68 (30.36%) and 66 (29.46%) reported being positive for HCV, HIV and co-infection, respectively. A higher proportion of HIV-infected cases was observed among women, (18.33% vs. 13.78% in men). Prevalence of HCV, HIV and co-infection were higher among participants with early onset of drug consumption, long periods of drug injection or who were unemployed. A positive serostatus was self-reported by 21(7.34%) participants who did not report any injection; among them 16 and eight, reported being positive for HCV and HIV, respectively; three reported co-infection. Only two people declared exchanging sex for money. For those that reported a negative test, the median time since the last HIV test was 11.41 months (inter-quartile range (IQR) 4-12) and for the HCV test was 4.5 months (IQR 2-7).
  
  
  CONCLUSIONS
  Among drug users in Catalonia, HIV, HCV and co-infection prevalence are still a big issue especially among IDUs. Women and drug users who have never injected drugs are groups with a significant risk of infection; this might be related to their high-risk behaviours and to being unaware of their serological status.
authors.affiliation: Department of Paediatrics, Gynaecology and Preventive Medicine, Universidad Autónoma de Barcelona, Barcelona, Spain. juliana.reyes81@gmail.com.|Drug Use Epidemiology Research Group, IMIM-Hospital del Mar Medical Research Institute, Dr Aiguader 88, 08003, Barcelona, Spain. juliana.reyes81@gmail.com.|Teaching Unit of Preventive Medicine and Public Health, PSMAR-UPF-ASPB, Barcelona, Spain. juliana.reyes81@gmail.com.|Public Health Agency of Barcelona, Barcelona, Spain. juliana.reyes81@gmail.com.
authors.forename: Juliana
authors.initials: J
authors.lastname: Reyes-Urueña
authors.affiliation: Public Health Agency of Barcelona, Barcelona, Spain. tbrugal@aspb.cat.|Institute of Biomedical Research Sant Pau (IIB Sant Pau), Barcelona, Spain. tbrugal@aspb.cat.
authors.forename: M Teresa
authors.initials: MT
authors.lastname: Brugal
authors.affiliation: Department of Health Government of Catalonia, Barcelona, Spain. xavier.major@gencat.cat.
authors.forename: Xavier
authors.initials: X
authors.lastname: Majo
authors.affiliation: Drug Use Epidemiology Research Group, IMIM-Hospital del Mar Medical Research Institute, Dr Aiguader 88, 08003, Barcelona, Spain. adomingo@imim.es.
authors.forename: Antonia
authors.initials: A
authors.lastname: Domingo-Salvany
authors.affiliation: Department of Paediatrics, Gynaecology and Preventive Medicine, Universidad Autónoma de Barcelona, Barcelona, Spain. jcayla@aspb.cat.|Public Health Agency of Barcelona, Barcelona, Spain. jcayla@aspb.cat.|Institute of Biomedical Research Sant Pau (IIB Sant Pau), Barcelona, Spain. jcayla@aspb.cat.|CIBER in Epidemiology and Public Health (CIBERESP), Barcelona, Spain. jcayla@aspb.cat.
authors.forename: Joan A
authors.initials: JA
authors.lastname: Caylà
mesh_terms: D000328:Adult; D060085:Coinfection; D003430:Cross-Sectional Studies; D055030:Drug Users / Q000706:statistics & numerical data*; D005260:Female; D015658:HIV Infections / Q000453:epidemiology*; D006526:Hepatitis C / Q000453:epidemiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012307:Risk Factors; D057566:Self Report; D012737:Sex Factors; D060386:Sex Workers; D013030:Spain / Q000453:epidemiology; D015819:Substance Abuse, Intravenous / Q000453:epidemiology*