This study aimed to provide data on HIV and HCV prevalence and risk behaviors among people who inject drugs (PWID) in three Croatian cities (Zagreb, Split, and Rijeka). Using respondent-driven sampling, researchers recruited 176 PWID in Zagreb, 255 in Rijeka, and 399 in Split. They found low HIV prevalence (0.2-0.3%) but considerable HCV prevalence (29.1-38.3%). Reported needle sharing was low (2.5-8%) but condom use with casual partners was also low (39.2-44.4%). The authors conclude there is a need to expand harm reduction services like needle exchange and increase HIV/

1. Copyright © 2016 Senad Handanagic, MD,
MSc; WHO Collaborating Centre for HIV
Surveillance, Andrija Stampar School of
Public Health, School of Medicine,
University of Zagreb, Rockefellerova 4,
10 000 Zagreb, Croatia
Phone: +385 1 4590 147;
E-mail: shandanagic@yahoo.com
Senad Handanagica, Ivana Bozicevica, Marta Civljakb, Zoran Dominkovica, Sandra Sevicc, Jelena Barbarica, Tatjana Nemeth Blazicd, Oktavija Dakovic Rodee, Josip Begovace
aWHO Collaborating Centre for HIV Surveillance, Andrija Stampar School of Public Health, School of Medicine, University of Zagreb, bAndrija Stampar School of Public Health,
School of Medicine, University of Zagreb; c
Department of Sociology, Faculty of Humanities and Social Sciences, University of Zagreb, d
Croatian Institute of Public Health, Zagreb;
eUniversity Hospital for Infectious Diseases “Dr Fran Mihaljevic”, School of Medicine, University of Zagreb
Background: There are limited data on HIV
and hepatitis C virus (HCV) epidemiology
among people who inject drugs ( PWID) in
Croatia. This study aims were to provide data
on HIV and HCV prevalence and sexual and
injecting risk behaviours a mong PWID in
Zagreb, Split and Rijeka.
Methods: Using respondent-dr iven sa mpling
(RDS) from November 2014 to February 2015
we recruited a total of 176 PWID in Zagreb,
255 in Rijeka and 399 in Split ( Figure 1).
Participants pr ovided biological specimens for
HIV and HCV testing and completed a
behavioural questionnaire. We used RD S
Analyst statistical package1
to calculate
weighted population estimate s and 95%
confidence intervals (CI) and Gephi2 sof tware
to visualize recruitment chains (Figure 1).
HIV and hepatitisCprevalence,andrelatedriskbehavioursamongpeople who inject
drugsin three citiesinCroatia:Findingsfrom respondent-drivensamplingsurveys
Results: The estimated median age of PWID was
33 years in Zagreb, 34 years in Rijeka and 37 years
in Split. In the month before the surve y, 2.5% of
PWID in Split, 5.6% in Rijeka and 8.0% in Zagreb
reported sharing non- sterile needles and syringes.
Many PWID injected opioid substitution therapy
(OST) in the month before the survey (57.0% in
Zagreb and 57.5% in Split and Rijeka,
respectively). Among PWID who had a casual
sexual partner in the past 12 months (ranging from
39.2% in Split to 44.4% in Rijeka) condom use
was low. A lthough HIV prevalence was low (0.2%
in Rijeka and Zagreb, 0.3% in Split), H CV
antibody prevalence was considerable (29.1% in
Zagreb, 31.5% in Rijeka, 38.3% in Split). HIV and
HCV testing coverage in the past 12 months was
insufficient (Figure 2).
Conclusions: We found a low-level HIV
epidemic and a sizable HCV epide mic among
PWID across all three cities. There is a need to
develop a comprehensive approach to harm
reduction and scale up the coverage with needles
and syringes exchange progra mmes, OST and
HIV and HCV testing services, as well as to
strengthen sexual health interventions due to the
presence of high-risk sexual behaviours.
Figure 2: Weighted population estimates of age, gender, condom use, prevalence of HIV and HCV antibody and
testing rates for HIV and HCV among people who inject drugs (PWID) in three largest Croatian cities, 2015.
Figure 1. Recruitment chains in respondent-driven sampling
(RDS) surveys in three largest Croatian cities, 2015; Green =
HCV negative, Purple = HCV positive, White = unknown test
result, S = initial respondent (seed)
Rijeka; N=255Zagreb; N=176 Split; N=399
1. Handcock MS, Fellows IE, Gile KJ. RDS Analyst: Software for the Analysis of Respondent-Driven Sampling Data, Version 0.51. 2014. Available at http://hpmrg.org
2. Bastian M., Heymann S., Jacomy M. (2009). Gephi: an open source software for exploring and manipulating networks. International AAAI Conference on Weblogs and
Social Media. Available at: https://gephi.org.
73,4%
15,0%
44,3%
6,8%
38,3%
7,0%
74,0%
8,0%
47,9%
20,2%
31,5%
21,5%
80,5%
22,3%
60,9%
13,2%
29,1%
13,5%
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Male ≤24 years old Condom used at
last sex with
casual partner
Tested for HIV
in past 12
months and
know the result
HCV antibody Tested for HCV
in past 12
months and
know the result
Split Rijeka Zagreb