Effective Interventions Unit
Examining the injecting practices of injecting drug users in Scotland
Chapter 1: Introduction
Background
There is considerable evidence that needle/syringe exchange provision has helped to control HIV transmission among injectors (IDUs) (Frischer et al, 1992; Goldberg et al 1996). Recent research has also shown that prescribed methadone reduces the frequency of injecting and sharing among methadone recipients (Hutchinson et al, 2000; Simoens 2002). Nevertheless, despite evidence that current interventions may be helping to reduce the spread of hepatitis C infection, the indications are that prevalence and incidence are both still very high.
It is estimated that 10,000 (44%) of Scotland's 22,800 current IDUs have been infected with HCV (Hay et al, 2001), of whom approximately 8,000 continue to be infectious.
A third of Scotland's IDUs reside in Glasgow (Hay et al, 2001). Between 1990-96 approximately 2,500 IDUs in Glasgow were interviewed and saliva-sampled as part of a worldwide WHO collaborative investigation of HIV prevalence and risk behaviours (WHO Collaborative Study Group, 1993). IDUs were asked to provide consent for the HIV and hepatitis testing of their saliva specimens and were asked questions about drug injecting behaviours and lifestyle. In early 1998, a hepatitis C test to detect antibodies in saliva became available (Cameron et al, 1999) and residual specimens which had been stored were tested.
Of 1,949 IDUs, recruited and tested between 1990 and 1996, 1,189 (61%) were found to be saliva antibody positive for HCV (Taylor et al, 2000a); of those who had begun injecting after 1992, following the extensive development of the Glasgow needle exchange scheme, almost one-third (27/87) were HCV antibody positive in saliva. The results indicated, moreover, that new infections were more likely to occur in the community, where new needle and syringes are available, than in the prison setting where prisoners have no such access; of those who began injecting after full implementation of Glasgow's needle/syringe exchange provision in 1992 and were found to be HCV saliva antibody positive, only one-third possibly acquired their infection in prison.
The 1990-1996 surveys, which were geared towards HIV, provided insufficient or no information about the specific aspects of injecting drug use such as the sharing of filters, water or spoons, which have also been implicated in the spread of HCV (Hagan et al 2001, Thorpe et al 2002).
In 1999 and 2001/2 two further cross-sectional surveys were undertaken in Glasgow, adopting the same sampling method and questionnaire as used in the 1990-1996 studies and including a new set of questions specifically related to HCV. The 1999 study investigated IDUs who had commenced injecting since 1990. Analysis showed that of 463 IDUs recruited, HCV prevalence was 45% (209/463) in saliva. Among those who had been injecting for less than two years, 25% (23/93) were HCV antibody positive in saliva (Taylor et al, 2000b). The 2001/2 survey examined injectors who had begun injecting since 1996. Of the 466 IDUs recruited to the study, 55.2% (257/466) were HCV positive in saliva. Among those who had been injecting for less than two years (i.e since 1999), 37% (55/147) tested HCV positive in saliva. Thus it was clear that HCV was continuing to spread among IDUs in the late 1990s and early 2000's. In the 2001/2 study, 65% (n=301) had injected with a needle and syringe previously used by someone else at least once in their injecting career, 71% (323/457), 75% (346/458) and 75% (309/413) had shared filters, spoons and water, respectively, when preparing to inject. (Taylor et al, unpublished data).
The 2001/2 study also included a qualitative component whereby injectors were interviewed in depth about their reasons for continuing to share injecting equipment in the era of needle exchange. Some of the circumstances in which IDUs reported injecting with needle/syringes previously used by someone else were:
suffering withdrawal symptoms,
inability to resist the immediate availability of injectable drugs,
lethargy and
trust in their injecting partners.
Some environments, particularly those where large numbers of IDU were gathered together, also facilitated the temptation to share injecting equipment. These included hostel accommodation and prisons. Sharing always took place when IDU did not have access to their own clean and unused needle/syringes, in some cases because the opening hours of needle exchanges and pharmacies were too limited and in other cases because these facilities were too far away (Taylor et al, in preparation).
These quantitative and in-depth interview approaches elicited much information about reported IDU behaviour and confirmed the continuing spread of HCV among recent initiates to injecting. From these study results it is apparent that more effective ways to prevent HCV infection need to be developed. This will only be possible, however, if the transmission dynamics of HCV among IDUs are fully understood. Studies to date have not allowed the reporting of the specific practices, as yet poorly understood, which may place the IDU at risk of HCV acquisition. We know that needle sharing is a key factor in HCV transmission - approximately one third of Scotland's injectors continue to share needles and syringes (ISD 2001) - and that this habit may be increasing (Taylor et al, 2001). However, we do not yet know enough about the actual injection preparation methods which may influence transmission, e.g. the types of filters used, frequency of re-use of filters, water or spoons, the possible exchange of body fluids through sharing of tourniquets, swabs, etc. This information is essential to inform the development of effective interventions.
Accordingly, funding was provided by the EIU through the Scottish Executive's Drug Misuse Research Programme, to undertake an in-depth observational study of the injecting practices of IDUs in Glasgow.
This study forms part of the EIU's programme of research in the area of hepatitis C infection (Effective Interventions Unit, 2003). In particular, the study findings will inform a laboratory based study of the safety, risks and outcomes from the use of injecting paraphernalia which is planned to begin at the end of 2003.
AimThe aim of the study was to examine the injecting practices of Scottish injecting drug users to a degree of detail not previously achieved in the UK. The specific focus was on practices that could potentially facilitate the transmission of HCV infection. Risk practices other than the direct sharing of needles and syringes were also of special interest as these are not so well understood.
Objectives
The objectives of the study were:
To identify and describe the various stages involved in the preparation of drugs for injecting.
To identify the quantities and types of items used in the preparation process, how they are used and where they were obtained.
To explore to what extent preparation methods vary between injectors.
To identify whether different preparation methods are used for different injecting sites.
To identify whether paraphernalia items are shared and with whom.
To identify the levels of hygiene used in preparation e.g whether hands are washed prior to injecting, whether injecting sites are washed or swabbed prior to injecting, cleanliness of preparation sites.
To identify how injectors first learned to prepare injections and inject.
To identify the factors which influence paraphernalia selection, including difficulties in access.
To identify knowledge and beliefs about level of risk attached to different practices and the use of different paraphernalia.
To describe injectors' exposure to and adherence to harm reduction advice around safer injecting and paraphernalia use.
This report is aimed at all those who are involved in the delivery of care and treatment to drug injectors, to the providers of harm reduction services and to those who decide harm reduction policy. It is hoped that the findings of this study will provide a better understanding of the complexities of drug injecting and thus the complexities involved in reducing risk behaviours for blood borne virus transmission. This, in turn, may help the development of more effective harm reduction policies.
The following report is divided into four chapters. Chapter 2 describes how the study was undertaken. Chapters 3 and 4 give the results from the study. Chapter 3 describes in detail the process of injecting and the frequency with which each part of the process occurs. To highlight the variation in injecting techniques and risk behaviours and also the influence on these of social settings. Chapter 4 provides a series of in-depth case studies. Chapter 5 discusses the results and draws conclusions.