Increasing the effectiveness of needle and syringe programmes

Needle and Syringe programmes have had significant success in many places (including the UK) in preventing HIV epidemics amongst injecting drug users. However, they have been unable to make significant inroads into the prevalence (i.e. the overall percentage of injectors who have) of hepatitis C amongst injecting drug users.

This article, which draws heavily on an excellent review 'hepatitis C and needle exchange' by Mike Ashton in Findings Magazine, will explore the methods by which neeedle exchange might be improved to the point where hepatitis C prevalence is reduced.

It also describes the features of service models which have been shown not to work, and looks at the emerging evidence on the role hepatitis C treatment can play in reducing prevalence.

Combining opiate substitution therapy (OST) and needle exchange is essential
Opiate substitution therapy is an essential component of blood borne virus prevention because it dramatically reduces the frequency and risk of injecting episodes: without it, the number of 'risk events' in the lives of injecting drug users who are opiate dependent are so high that avoidance of hepatitis C in particular is difficult.

The key to preventing epidemics of BBV's amongst injecting drug users is to combine effective OST with adequate needle and syringe provision thereby reducing the number of injections as much as possible, and reducing the reuse and sharing of injecting equipment.

One without the other will not be enough.

Coverage is crucial
As a public health measure the number of syringes given out, and the proportion of injecting drug users who get all the injecting equipment they need, are critical factors. There are many definitions of 'coverage' but the most useful one (because it is a measure that can be correlated with blood borne virus prevention) is the percentage of injecting drug users who have access to all the injecting equipment they need.

There is a 'dose/response relationship' - if you don’t give enough equipment to enough injectors, it doesn’t work. And if all injectors were given more needles and syringes than they needed to have one for every injection, then a sterile needle and syringe would be to hand at (almost) every injecting episode, and sharing would quickly drop well below the levels required to sustain blood borne virus epidemics.

However, rarely is it possible to increase the volume of equipment distributed out by syringe exchange schemes to hit this target.

This dose/response relationship was calculated by researchers at the department of social medicine at the University of Bristol, who mathematically modelled the HCV epidemic using the information from their study of HCV incidence in UK cities.

WIthout combination quality Opiate Substitution Therapy (OST) and needle exchange they calculated that HCV prevalence would rise to around 80% - and this has indeed been the experience of places who have not introduced a coordinated harm reduction response. By increasing the number of injectors who have access to OST and enough injecting equipment to 80% they calculated that in 20 years HCV prevalence could be reduced to under 20%.


Why isn't coverage always adequate?
Commentators who point to the limitations of needle and syringe programmes acknowledge that a key limitation is that there is simply not enough of it (Crofts 1999).

A major reason why some studies find NSP have not been delivering enough equipment (Sharma 2003) is that the exchanges they have studied have engaged in ‘trickle-feed’ equipment supply, feeding needles and syringes into infection-spreading drug injecting patterns rather than overwhelming these with the volume and accessibility of sterile equipment (Bruneau 1997, Remis 1998)

Often supplies are constricted because the money to fund services for drug misusers is hard-won and particularly so for services which are seen as accepting of their lifestyles. The funds which are allocated may be trammelled with restrictions such as overly strict one-for-one exchange and limits on quantities (Canadian HIV/AIDS Legal Network 1999, Bray 2001) opening hours, and locations.

Sometimes, the restrictions are a misguided attempt to induce frequent attendance (Strike 2002), limit the frequency of injecting, prevent re-sale of needles and syringes, stop them being used to initiate new injectors, or to ensure safe disposal of used equipment. Sometimes too, such restrictions are an attempt to deflect public opposition (Bardsley 1990) or reflect the staff’s perceptions of syringes and needles primarily as objects which pose a risk to injectors and to the public rather than as the means to avoid infection.

Matching distribution to need
Sheer volume may not in itself be sufficient: the supply of equipment may need to be micro-managed to ensure that it reaches all the places injecting occurs and fresh supplies are needed (Power 1996).

Despite overall abundance, limits on the times and places when equipment can be obtained can create a mismatch between availability and need, especially when cocaine binges suddenly escalate the rate of injection (Patrick 1997).

A defining feature of the life of many drug users is a narrowing of horizons and of repertoires of behaviour down to accessing and using drugs. One consequence may be a constricted circle beyond which they will not (metaphorically or actually) travel to obtain sterile injecting equipment, typically in distance a mile or two and no further (Mason 1998, Stimson 1988, Hunt 1994).

Providing local services may improve attendance rates, (Monterroso 2000) and reduce sharing of injecting equipment (Hutchinson 2000).

Proximity is not the whole answer. Intoxication, sedation, the desire for the next cocaine or speedball high, the temptation of having the drug to hand, can all make seemingly small access hurdles too high (Harvey 1998). Drug users may lack not only the psychological but also the material resources to access needle exchanges.

Where an NSP is conveniently located within a circumscribed, small area of injecting drug use, the answer may simply be longer hours.

Elsewhere improving access may require diversification to venues such as all-night pharmacies, outreach workers (Taylor 2000) mobile exchanges, 24-hour vending machines (Obadia 1999), and accident and emergency departments.

In other cases it is about specifically identifying and targeting ‘hotspots’ when even extensive NSP provision can leave injectors with drugs but without sterile injecting equipment.

Examples are Vancouver’s welfare hotels, America’s shooting galleries, and perhaps too amphetamine injectors in the north west of England who tended to share before a group leisure outing. In these situations the service will need to be there either directly or via peer outreach (Archibald 1998).

Mobile or peripatetic NSP seems an ideal solution, but if they operate for only a short time in each area there is a high chance that they will be missed and that sharing will occur as a result (Miller 2002).

Some NSPs arrange home delivery and collection, likely to be particularly useful for injectors wary of carrying syringes in the street or of being identified using the exchange, but sometimes an unnecessary use of resources. Both tactics have a particular place in rural or other areas where injectors are thinly spread across a wide area.

All the equipment, all the time
Improving perfomance will require both increasing the scope of the core equipment exchange/supply function, and accompanying this with interventions which further reduce the risk of infection.

A priority elevated by hepatitis C is to widen the focus to potentially contaminated injecting equipment other than needles and syringes. This ‘paraphernalia’ includes filters, spoons to heat drugs in, water to clean and flush syringes and to dissolve drugs, and acid used to dissolve heroin and crack cocaine.

NSPs historically have a distinctly poor record at preventing paraphernalia sharing (Sears 2001). Providing these materials is an important first step which paves the way for education, training and peer interventions to combat their re-use.

Not providing them may send an implicit message to customers that sharing these implements is not a risk. Certainly there is a demand from British injectors for NSPs to supply sterile water, filters and acid (Clarke 1998).

Meeting this demand is likely to be most important for people without their own homes who cannot, for example, just reach for a fresh spoon or boil water to sterilise a used one, and who may not even have a tap to draw water from (Gillies 2002).


Increasing frequency of attendance
Frequent access to clean equipment, and the opportuntiy to have used syringes disposed of cuts down the time used equipment remains in circulation, and helps ensure that users get enough to meet their needs without having to stockpile large amounts of equipment.

Sporadic attendance is a common (but not universal) obstacle to achieving this ideal (Stimson 1988, Vellerman 1989). One repeatedly reported deterrent to attendance is the fear of being stopped by the police while carrying needles and syringes to or from the exchange (Hunt 1996). As a result, one-for-one exchange where visitors have to travel to the service is likely to mean that used equipment stays in circulation for longer, increasing risk (Strathdee 1997).

One solution is to be able to convincingly reassure injectors that their fears are unfounded by gaining the cooperation of local police. Drug user networks can quickly spread the news, making a big difference to attendance (Sarang 2001). The same communication channels mean that hard-won gains can quickly be reversed if just one officer on one occasion steps out of line.

Another partial solution is to arrange for safe disposal options which do not require return of used syringes to the NSP, such as home pick-ups or safe disposal bins.

These efforts can be thwarted by instability in injecting locations and in addicts’ lifestyles which mean they cannot be guaranteed to inject adjacent to a bin or to be there when the NSP worker calls (Hammett 2003).

Fear of being identified as an injector either by police or within one’s community also deters attendance at exchanges (Robles 1998, Sergeyev 1999) and vending machines, regardless of whether using these facilities entails carrying needles and syringes. In the final analysis, only destigmatisation and the irreversible lifting of sanctions on injectors engaged in health-promoting activity will completely solve these kinds of problems.

In the UK the provision of sterile water and sachets of the acidifiers needed to dissolve heroin and crack cocaine have been shown to increase frequency of attendance at NSPs – syringes, when they run out can be re-used, but if you've run out of citric then you've got to get some from somewhere, and if it's from the NSP, then the visit to collect more will be an opportunity to collect more injecting equipment, and dispose of used syringes.


Proactive intervention
Physical coverage of injectors and injecting occasions with needles and syringes is necessary but may not be sufficient to eliminate risk behaviour.

Some proactive engagement with injectors may be needed, as studies NSPs which have not made a major impact on risk behaviour have commonly adopted, or been forced to adopt, a non-interventionist stance. Particularly when syringes and needles are readily available from pharmacies or other sources, the result may be that NSPs create no added risk-reduction (Vlahov 1998, Hagan 1999). In Amsterdam, their most noticeable impact was to reduce the need felt to re-use one’s own equipment, rather than to eliminate re-use of other people’s.

There is also a role for needle exchange in encouraging treatment entry and a move way from injecting and drug use, but without jeopardising the accepting, non-judgemental ethos of harm reduction.

A needle exchange is definitely not the place where someone who chooses to inject should feel admonished or pressurised to stop. Nevertheless, injectors will sometimes choose not to inject someone else, choose not to promote injecting, choose to use other routes of administration, or choose to reduce or stop their drug use. At the least they can be supported in these decisions, at best provided sensitive encouragement to take these decisions and the means to implement them.

Such interventions give added value to NSP in a way that will be increasingly sought by purchasers required to justify the extra investment compared to pharmacy-based schemes. Extra services can also aid coverage by attracting more visitors (Anthony 1995).

Intervening appropriately hinges on first assessing the risks run by visitors to the NSP. Assessment could itself have a risk-reducing impact and encourage injectors to arrange for HIV and hepatitis tests. This essential step has sometimes been lacking.

Staff will then need the skills and confidence to work in ways which maximise behaviour change without alienating the service’s users. The skills are probably similar to those deployed by practitioners of brief interventions in settings where the recipient is, from their point of view, attending for another purpose.

Sometimes staff feel unable to take on this role because they lack sufficiently detailed knowledge of injecting and injecting-related risks or lack communication skills. Proactive intervention is also predicated on a management which fosters the confidence and skills of staff and provides safe opportunities to admit when these are lacking.

Interventions may focus on information and awareness of unconsidered risks ­ such as ‘backloading’ or needlestick injuries. They may involve the development of skills to manage particularly persistent and difficult situations such as sharing between sexual partners. They can give guidance on the prevention and management of overdose and can also involve the provision of lowthreshold access to a range of other primary care services such as viral testing, sexual health promotion, hepatitis B vaccination and general health checks.

Increasing access to hepatitis C treatment
Martin et. al published an article in the journal Hepatology that calculated the cost-benefit of treating current and former injecting drug users who are HCV positive with anti-retroviral drugs, which have a cure rate of in excess of 60%.

They found that in the UK less than 1 in 100 injecting drug users are being treated for hepatitis C, but were able to calculate that if this were increased to 20 per 1,000, (alongside quality OST and needle exchange) hepatitis C prevalence amongst injectors in a population where 40% were HCV +Ve could be reduced to 34% in 5 years, 28% in 10 years, and 20% in 20 years. This represents an effective and cost-effective route to significant gains in BBV prevention, and indicates that developing effective, accessible HCV testing and treatment should be a priority for all harm reduction services.

Increasing access to drug treatment
Contact with needle exchange workers can also enable referral to treatment services, particularly Opiate Substitution Therapy. Needle and syringe programmes attract the highest risk and most dependent drug users – frequent injectors – among whom in Britain, treatment achieves the greatest social and health benefits (Stewart 2000).

If successful treatment referral can be integrated into needle exchange work and it certainly can (Paone 1997) – the benefits are substantial.

One suggestion is that needle and syringe programmes interview attenders monthly to identify those whose injecting is accelerating (they will also tend to be the consistent attenders)(Marmor 2000), who would attract special efforts at referral to treatment. A reverse referral of treatment relapsers to needle and syringe programmes is also an important care pathway.

Treatment and needle and syringe supply can also have a synergistic impact on risk behaviour. By reducing drug use and especially the frequency of injecting, treatment reduces the opportunities for the sharing of injecting equipment (Metzger 1998) and relieves some of the pressure on exchanges. In the meantime, the role of NSP is to reduce the need for each episode of injecting to involve re-used equipment and to take potentially contaminated equipment out of circulation. Treatment can also address the lifestyle factors which underlie continued sharing.

Evidence for synergistic impact is apparent in Britain and in the USA. In the early years of needle and syringe supply in Britain, when injectables were more widely prescribed than today, facilitating access to this treatment was probably one of the main ways NSPs reduced infection risk.

At Baltimore’s NSP, 160 attenders were offered a guaranteed place at a local methadone maintenance clinic. Within the time frame of the study just over half turned up. A creditable 76% completed at least three months of treatment, just 12% less than other patients. Due to a reduction in injecting frequency, the number of days on which they shared needles fell from nearly five in the month before entering treatment to two days in the following month.

Where NSPs do not have suitable options to refer to, they can still use their unique access to out-of-treatment injectors to encourage service development by publicising the gaps and the reasons why injectors are not willing to attend or do not respond well to existing services. Similarly, NSPS can act as advocates for housing, welfare and other services which can tackle the material deficits and psychological problems that breed risk behaviour.
Working with networks
Leading drugs and HIV researchers here in Britain and the USA (Stimson 1996) believe that further progress in risk reduction requires a shift from targeting individuals to targeting networks and the group norms which sustain risk behaviour and make it resistant to change.

In this vision the NSP’s customers are not just the recipients of services but collaborators in the creation of a more health promoting community.

Helping to shape the service to their requirements is a basic role for NSP users, and a particularly important one in countries such as Britain where NSPs compete against pharmacy sales and supplies of equipment from other injectors.

In the Netherlands and Australia it is not unusual for drug users’ organisations to themselves manage NSPs (Loxley 2000).

Beyond consulting NSP users over service delivery is actually engaging them in delivering the service. Practically from the start needle and syringe programmes have exploited sharing networks by supplying attenders with sufficient equipment for them to pass on sterile syringes to their contacts.

Limits on the quantities NSPs will supply which are so low as to effectively prohibit the practice are the main impediment. Where limits are not enforced or are more liberal, ‘secondary’ distribution of sterile equipment can be very common in Britain (Speed 2002) and elsewhere, in some areas making an important contribution to the reach of the service (Valente 1998).

San Francisco illustrates the potential of peer exchange in a circumscribed community small enough for the networks to be personal, and for the peer exchangers to be in contact with a high proportion of local injectors.

Four secondary syringe exchangers recruited from the residents of a camp used by young homeless injectors were trained by a local community agency (Valente 1998) Each recruited a small crew of helpers with a view to maintaining a 24-hour service supplying syringes and needles and a range of other injecting equipment.

They achieved high penetration. Over the past month 85% of interviewed injectors who frequented the camp had regularly used (over three times) a secondary exchange service compared to under 1 in 5 at comparison sites.

Injection risk behaviour remained common in both groups but was less at the intervention site, where 40% had shared a needle in the past 30 days and 27% had re-used filters compared to 69% and 49% respectively at the comparison sites.
Once other factors had been taken into account, needle sharing was nearly four times more likely at the sites where secondary exchange was not operating. For various reasons this evidence is not conclusive but it is suggestive of a strong risk-reduction effect.

Employing injectors and ex-injectors to conduct outreach among their networks, and to recruit other HIV risk-reduction advocates, is a well established tactic (Neaigus 1998).

In Baltimore potential peer leaders were identified simply by asking injectors to nominate people who drug users might listen to about preventing HIV transmission and then to bring them in to be interviewed (Latkin 1998). Eight in ten of the these ‘opinion leaders’ were themselves injectors. There was strong evidence that participating led the leaders to reduce their HIV risk behaviour and suggestive evidence of a similar impact among their contacts.

Another approach has borrowed from pyramid selling techniques and incorporated quality check mechanisms into its reward structure. Noting that younger injectors rarely turn up at NSPs, an Australian project recruited young injectors, taught them about hepatitis C transmission routes, and paid them to teach other injectors who returned to the project to be ‘examined’, for which the examinees received a fee (Preston 2001).

Extra payments were made to the peer educators if their pupils got high marks. The same type of intervention has been implemented in the USA and replicated in Russia, where the exchange became heavily dependent on a few direct users who distributed large amounts of equipment to people unwilling to visit the centre. Injecting in the area was primarily recreational and social, conducive conditions for secondary exchange. This was made more important by the fact that police surveillance deterred attendance at the mobile exchange.

Quality check mechanisms such as those integrated in the US and Russian projects are important to prevent off-message or off-putting communications from self-appointed opinion leaders.

Other methods trialed in the USA involve bringing together groups of injectors to discuss HIV risk and how to avoid it and some studies show greater risk reduction than individual approaches. In one injectors were simply asked to bring in their syringe-sharing contacts.

Which type of network intervention is feasible will depend on the social relationships between local injectors. Where these are relatively stable and based on ties that go beyond occasional collaboration in drug procurement and use, natural groups can be co-opted and existing relationships used to exert influence and spread information. Elsewhere interventions may need to identify the few persistent participants in an unstable social network.

Opportunities to prevent initiation into injecting
NSP was originally developed to perform a secondary prevention role, namely avoiding the acquisition of HIV infection among people who have begun injecting. This remains (and will always be) it’s key objective.

However, it is increasingly clear that:

• Other primary health care activities can be performed as part of syring exchange;

• It is feasible to conduct primary prevention work – which prevents the initiation of non-injectors as part of syringe exchange.

Consequently, where it is possible to prevent people beginning to inject, this is a valuable goal. In an evaluation of a brief intervention used with current injectors, Hunt et al (1998) describe how such intervention work can be undertaken.

The intervention is based on the following insights from research:

• Existing injectors initiate the majority of new injectors;

• Observing injecting is very influential in moving non-injectors from disapproval towards trying injecting

• Frequently, injectors are unaware of the impact of injecting in front of non-injectors

• A proportion of injectors lack the skills to manage requests to initiate a non-injector, even though they would prefer not to do so.

The intervention has five main objectives, which were to:

• Raise the topic of initiation and allow the initiation of others to be better considered and anticipated;

• Increase participants awareness of risks to themselves as initiator and the person being initiated;

Reduce the occurrence of activities that may inadvertently increase initiation of others into injecting;
Increase competence in managing some commonly occurring scenarios where initiation is requested;
To increase disapproval of initiation and reluctance to initiate others.

Beyond needle and syringe programmes
The promotion of safer injecting practice forms a cornerstone of needle and syringe provision policy but also of other community interventions.

Raising the topic of safer injecting and providing appropriate understandable information to clients and into injecting networks should be an essential element in the work of any service which aims to meet the needs of drug users.
In this respect addiction treatment is an important opportunity. To the extent that the core treatment process reduces drug use and especially the frequency of injecting, it will also reduce the number of times injectors can risk sharing injecting equipment and potentially becoming infected (Metzger 1998).

Treatment should also be a venue for direct risk reduction advice and interventions. One US study collated results from HIV risk reduction interventions conducted during drug treatment programmes (Prendergast 2001).

It found these effective in reducing sexual risk behaviour and improving risk-reduction skills such as coping and self-control. Risky injection practices themselves were not significantly reduced, but this could be because measures were generally taken while the drug user was still in treatment and towards the end of that treatment. Improvements in sexual behaviour and in skills suggests that such interventions could prevent reversion to risky injecting once users had left treatment or among injectors not in treatment.

We may also be able to learn other lessons from the USA where NSP has previously not been possible and the stress has been on alternative anti-infection tactics.

Substantial investment has been devoted to two federally funded programmes researching outreach. While the intervention began with the first contact, the main purpose was to bring injectors back to clinics, offices or other ‘off street’ locations for one or two brief sessions (totalling an hour or less) of HIV testing and counselling, risk reduction advice, and skills training (Coyle 1998).

There were no control groups but the overall pattern of findings suggests a consequent reduction in the numbers injecting, in injection frequency, in crack use, and in the re-use of needles and syringes and other injecting equipment, and more frequent decontamination of used equipment, all protective against infection.

Typically about 1 in 5 of the people who had been re-using syringes and needles before the intervention were no longer doing so afterwards, or were sharing less often. For other injecting equipment, the corresponding proportion was about 1 in 4.

There is also some evidence that risk reductions achieved by this type of intervention feed through to reduced incidence of HIV infection.

Techniques modelled on motivational interviewing and cognitive therapy may also be worth trying (DoH 2001) The aim might be to generate motivation for behaviour change by making it more difficult to engage in risk behaviour and yet still see oneself as a ‘responsible’ injector. These motivation enhancers may need to be supplemented by training in the personal skills needed to avoid risky behaviour and by measures to foster the material and social resources needed to implement health promoting practices. Practical skills are also needed such as how to inject more safely and how to maintain a high standard of hygiene.

Findings magazine
We are very grateful to Mike Ashton of the excellent Findings Magazine for his permission to draw heavily on his excellent article 'hepatitis C and needle exchange' to write this article.

Findings magazine is a goldmine of evidence on drug and alcohol to open the Findings website in a new window, click here.

To read the findings article 'Hepatitis C and needle exchange', click here.

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ALCOHOL CONCERN - DRUGSCOPE - NATIONAL ADDICTION CENTRE
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