High variability of HIV and HCV seroprevalence and risk behaviours among people who inject drugs: results from a cross-sectional study using respondent-driven sampling in eight German cities (2011–14)

Abstract

BackgroundPeople who inject drugs (PWID) are at increased risk of acquiring and transmitting HIV and Hepatitis C (HCV) due to sharing injection paraphernalia and unprotected sex. To generate seroprevalence data on HIV and HCV among PWID and related data on risk behaviour, a multicentre sero- and behavioural survey using respondent driven sampling (RDS) was conducted in eight German cities between 2011 and 2014. We also evaluated the feasibility and effectiveness of RDS for recruiting PWID in the study cities.MethodsEligible for participation were people who had injected drugs within the last 12 months, were 16 years or older, and who consumed in one of the study cities. Participants were recruited, using low-threshold drop-in facilities as study sites. Initial seeds were selected to represent various sub-groups of people who inject drugs (PWID). Participants completed a face-to-face interview with a structured questionnaire about socio-demographics, sexual and injecting risk behaviours, as well as the utilisation of health services. Capillary blood samples were collected as dried blood spots and were anonymously tested for serological and molecular markers of HIV and HCV. The results are shown as range of proportions (min. and max. values (%)) in the respective study cities. For evaluation of the sampling method we applied criteria from the STROBE guidelines.ResultsOverall, 2,077 PWID were recruited. The range of age medians was 29–41 years, 18.5–35.3 % of participants were female, and 9.2–30.6 % were foreign born. Median time span since first injection were 10–18 years. Injecting during the last 30 days was reported by 76.0–88.4 % of participants. Sharing needle/syringes (last 30 days) ranged between 4.7 and 22.3 %, while sharing unsterile paraphernalia (spoon, filter, water, last 30 days) was reported by 33.0–43.8 %. A majority of participants (72.8–85.8 %) reported incarceration at least once, and 17.8–39.8 % had injected while incarcerated. Between 30.8 and 66.2 % were currently in opioid substitution therapy. Unweighted HIV seroprevalence ranged from 0–9.1 %, HCV from 42.3–75.0 %, and HCV-RNA from 23.1–54.0 %. The implementation of RDS as a recruiting method in cooperation with low-threshold drop in facilities was well accepted by both staff and PWID. We reached our targeted sample size in seven of eight cities.ConclusionsIn the recruited sample of mostly current injectors with a long duration of injecting drug use, seroprevalence for HIV and HCV varied greatly between the city samples. HCV was endemic among participants in all city samples. Our results demonstrate the necessity of intensified prevention strategies for blood-borne infections among PWID in Germany.Electronic supplementary materialThe online version of this article (doi:10.1186/s12889-016-3545-4) contains supplementary material, which is available to authorized users.

A large proportion of people who inject drugs are susceptible to hepatitis B: Results from a bio-behavioural study in eight German cities

“…Between 76% and 88% of participants reported injecting in the last 30 days, and 57-85% reported heroin consumption in this period. Other characteristics and drug consumption practices of the study population have been published elsewhere (Wenz et al, 2016).…”

“…RDS is an adequate sampling method to reach PWID. However, after evaluating the method in this study, it was decided against presenting RDS-weighted results, as some of the necessary assumptions for weighting were not fulfilled in all study cities (Wenz et al, 2016). Selection bias due to oversampling of persons with communicative competence and who understood the study flow cannot be excluded.…”

“…All participants attended a questionnaire-assisted interview and provided a capillary blood sample. Detailed information on the study design and recruitment process has been published previously (Zimmermann et al, 2014;Wenz et al, 2016).…”

Prevalence of HCV among people who inject drugs in Brussels—a respondent-driven sampling survey

“…Based on expert opinions from key stakeholders including PWID and service providers, the PWID population in Brussels was estimated at between 500 and 1000, but apart from treatment centers and other community-based supportive groups, there were no users groups of PWID, and the connections between PWID were supposed to be weak. As standard probability methods are generally difficult to apply to hard-to-reach populations such as PWID [13] and because the hidden nature of injecting drug use decreased the potential for success of other survey strategies such as time-location sampling or simple random sampling, respondent-driven sampling (RDS) was chosen as the sampling method. It was decided to include also highrisk opiate users (HROU) in the study.…”

Stellungnahme zur vorläufigen Bewertung des IQWiG zum Nutzen eines Screenings auf Hepatitis C

“…Diese Maßnahme ist besonders wichtig für Infektionen mit einer hohen Prävalenz in einer definierten Gruppe. Studien zeigen, dass die am stärksten betroffene Gruppe hinsichtlich einer HCV-Infektion in Deutschland Personen sind, die sich Drogen injizieren [16,17].…”