Strategies for the prevention of HIV infection among and from injecting drug users

Sections

ABSTRACT
Introduction
Education of injecting drug users
Reducing high-risk behaviour among injecting drug users
Human immunodeficiency virus testing
Provision of safer injecting equipment
Decontamination of used Injection equipment
Provision of safer sex equipment
Treatment
Outreach
Organizations of injecting drug users
Research
Managing high-risk injecting drug users whoknowingly infect others
Prisons
Conclusion

Details

Author: A. WODAK , D. C. DES JARLAIS
Pages: 47 to 60
Creation Date: 1993/01/01

Strategies for the prevention of HIV infection among and from injecting drug users*

A. WODAK Director, Alcohol and Drug Service, St. Vincent's Hospital, Darlinghurst, New South Wales, Australia
D. C. DES JARLAIS Beth Israel Medical Center, New York, New York, United States of America

ABSTRACT

Despite a substantial reduction in the level of high-risk, behaviours among injecting drug users (IDUS) documented in an impressive number of studies from many countries, human immunodeficiency virus (HIV) infection continues to spread among and from this population, reflecting the high baseline levels of these risk behaviours before the epidemic. In many countries, the control of HIV spread among IDUs is critical to efforts to control the epidemic in the population as a whole. Although the evaluation of individual or multiple strategies is problematic, there is accumulating evidence and increasing confidence that the course of the epidemic can be altered by implementing some or all of a range of strategies. Authorities mindful of their public health responsibilities should estimate the risk of spread of HIV among and from IDU populations in their jurisdiction and plan their response accordingly by selecting prevention measures that are appropriate for local conditions and by vigilantly monitoring developments.

Introduction

HIV infection among IDUs has been recognized in over 50 countries, continues to spread in countries where it has become established and is being detected in a growing number of countries. Nevertheless, there is increasing evidence that early, vigorous and widespread implementation of a comprehensive range of prevention strategies appears to alter the course of the epidemic. The results of implementing prevention strategies when the epidemic has already become established are less satisfactory but still considered worthwhile. This paper surveys the range of available prevention strategies. Space does not permit examination of the evidence of effectiveness of these strategies individually or collectively. This paper also does not include more general strategies such as measures intended to reduce the number of IDUs in a population, although obviously these may be of particular importance in the long term.

*This paper was derived from a chapter in a document prepared for the Global Programme on AIDS, World Health Organization.

Education of injecting drug users

For effective education of IDUs, the diversity of drug injectors must be recognized and subpopulations targeted specifically. It is therefore important that the characteristics of local IDUs are known and that they influence the design of health education.

Most drug injectors are aged between 18 and 45, with male drug users usually far more numerous than female drug users. Information about the characteristics of IDUs in developing countries is limited. The frequency of drug injecting varies over an extremely wide range. Some inject 10 or more times a day, especially if the drug of preference is cocaine on its own or in combinations. Others may inject as infrequently as once a month. Some will inject in binges separated by months of abstinence. It is not at all unusual for even severely dependent drug injectors to have several periods of voluntary abstinence a year. Some may inject drugs as a form of recreation and then inject regularly in a highly dependent fashion before switching back again to lower levels of use. Most prefer to inject their favourite drug, but a minority will utilize a variety of routes of administration. In many countries, the indiscriminate use of a wide variety of psychotropic substance has become common. Although IDUs come from all social and economic strata, the majority are drawn from poorer, less-well-educated and lower-social- status groups. In some countries, ethnic minorities are overrepresented. Some strongly identify with the drug-using subculture, while others, despite injecting even more frequently, prefer to consider themselves simply as persons who inject drugs from time to time. Some persons inject drugs occasionally for long periods, retaining apparent control of their drug use, avoiding drug-related problems and maintaining continuity of employment. Whether these so-called "recreational' IDUs are more or less numerous and at a greater or lesser risk of HIV than regular and dependent IDUs is uncertain and may vary from country to country. Almost 50 per cent of IDUs in most countries are likely to have spent some time in prison. This proportion is usually even higher for males than females. The appearance of IDUs is also far more diverse than the stereotype. While some may prefer to adopt clothing styles strongly identified with the drug subculture, others may be well-educated, employed, conventional-looking and relatively well-nourished. Youth at high risk of drug use tend to be from a lower socioeconomic background and unemployed, and they often have a history of some deviant behaviour such as petty theft.

It is often assumed that behaviour changes only after attitudes change, which itself requires a change in knowledge. The reality is far more complex. Sometimes behaviour change occurs through the influence of peers and is followed by changes in attitude and knowledge. IDUs are usually very well informed about the facts of HIV/AIDS. Most are reasonably realistic about the chances of other IDUs acquiring HIV, but they may be unwilling to accept that they are personally exposed to high levels of risk.

Unrealistic and unachievable goals are often set for health education directed at IDUs, causing it to be dismissed as an intervention. Expecting complex, highly reinforced behaviours to change following a mass media campaign or exposure to a single pamphlet or poster when the possible loss of relationships, liberty, health, financial security or career has already been insufficient to produce behaviour change is asking a great deal of education. Even modest behaviour change is unlikely to occur without some education; conversely, behaviour change is not inevitable following exposure to health education. Also, behaviour is unlikely to change if the means for achieving that change, such as sterile needles and syringes, are not available.

The content of health education must be credible and the presentation acceptable to the target population. The sensitivity of most communities to injecting drug use must be acknowledged. Inevitably, the content, explicitness and manner of presentation possible in some communities may be less satisfactory than health educators would wish.

Some IDUs will be learning about HIV/ AIDS for the first time, while for others health education will reinforce knowledge acquired earlier from peers or previous campaigns. As there is a high rate of recruitment and exit from the pool of IDUs, it is important that educational interventions should be designed to suit both new recruits and those with a long history of drug injecting.

The aim of educational interventions may vary from discouraging would be drug users from experimenting with illicit drugs to discouraging the practice of injecting among those already taking drugs by non- parenteral means to discouraging the sharing of injecting equipment among those who are already injecting or at risk of injecting. In some countries it might be appropriate to attempt to reduce the practice of injecting, and the high risk of subsequent sharing, by increasing awareness of alternative non-parenteral methods of consuming illicit drugs. It is also important to emphasize that HIV infection can be transmitted not only by the sharing of needles and syringes but also by the sharing of injection paraphernalia. IDUs must be reminded that spoons, bottle tops, cotton wool and materials used to draw up and prepare for the injection can all become contaminated and cause infection. As it may not be possible to eliminate the reuse of needles and syringes, education should also teach the decontamination of used injection equipment. Even in areas where sterile needles and syringes are readily available, some reuse of injection equipment takes place, especially between regular sexual partners.

The education of IDUs should encourage the responsible disposal of used injection equipment. IDUs have responded favourably to reminders that thoughtlessly discarded used equipment may jeopardize the survival of programmes that increase the availability of sterile injection equipment [1] . Authorities can help by improving disposal facilities.

Alcohol and drug workers often need to be taught how they can advise IDUs about safer sexual behaviour and less hazardous methods of consuming drugs. Outreach workers may be especially well placed to provide sterile needles and syringes and decontamination and safer sex equipment and to promote entry into drug treatment services. Attempts to reduce needle - sharing among IDUs have generally been more successful and have overshadowed efforts to reduce unsafe sex practices. Education to reduce unsafe injecting or sexual practices is more likely to be effective if it is explicit and anticipates barriers to the implementation of safer behaviour.

Some health workers strongly committed to the promotion of absti- nence may feel very uncomfortable with approaches that recognize the difficulty of eliminating risk among IDUs. They regard measures such as providing sterile injection equipment as tantamount to condoning an illicit behaviour. There is no simple answer to this complex web of professional and public health considerations. The training of treatment staff must allow an opportunity for values to be clarified and should encourage the tolerance of diverse views. Staff committed to the promotion of abstinence should recognize that colleagues who focus more on public health are also making a valuable contribution and vice versa.

The importance of sexual transmission of HIV from drug users to their sexual partners requires that health workers also be trained to deal sensitively with sexual behaviours. This involves more than mere advice to abstain from sexual activity or to use condoms properly. Drug users may need to learn to negotiate safer sexual behaviour and to be encouraged to consider family planning as a means of reducing vertical transmission.

Comprehensive education for drug and alcohol workers regarding the sexual transmission of HIV should be sensitive to cultural values and gender roles. Nevertheless, HIV does not respect cultural values, and some cultural change may be needed to reduce sexual transmission. Staff working with IDUs will probably need to examine their own beliefs and anxieties about sexual behaviour before they are able to be effective counsellors for others.

The same considerations that apply to alcohol and drug workers also apply to general health and welfare professionals. Attitudinal problems in this group are probably of even greater importance. Many may initially object to helping IDUs, so their education and training needs to be conducted with tact, have modest objectives and take matters slowly. Emphasizing the critical role of IDUs in the control of HIV infection for the general community may persuade some reluctant general health workers to support initiatives that they did not at first support.

The control of the IDU component of the HIV epidemic may conflict with the training and cultural values of staff f in other sectors, such as policy makers, prison officers, police and welfare staff. Education and training for these special groups is therefore very important. Since many of the strategies required to control the HIV epidemic among IDUs can only be successful if supported at ministerial, bureaucratic and local levels by health department officials working with other sectors, including especially law enforcement, these special groups may need to be educated even on relatively basic aspects of HIV/AIDS.

Controversial strategies may be required to contain the epidemic. It is not possible to control HIV infection in IDUs without strong community support. Therefore, mass campaigns and other educational interventions that inform the community about the possible consequences of an uncontrolled epidemic play an important role. Political leaders also cannot venture too far ahead of community attitudes. Educating the community also serves to educate key decision makers in the bureaucracy. it is important that the media are encouraged to be sympathetic to the subject. Time spent briefing journalists is often a productive investment. Political committees whose members hold divergent views can be helpful in working out compromises that can be gradually strengthened. Pilot studies can also be used to test public reaction to controversial issues. Over time, hostility may dissipate, and then the original intervention can be extended. A distinguished visiting international expert may also be able to lend credibility at a time when local advisers remain unheeded because they are considered to have "known positions'. Committees, advisory bodies, reports and conferences can all contribute to the development of an appropriate response to the epidemic.

Reducing high-risk behaviour among injecting drug users

IDUs probably receive most of their initial counselling from general health and welfare workers, but thereafter counselling on a regular basis is usually provided by more specialized staff. These interactions provide a good opportunity to disseminate or reinforce knowledge and change attitudes to facilitate a reduction in risk -taking behaviour. The counsellor may tell the IDU about the availability of sterile needles and syringes, provide instruction on the decontamination of injecting equipment and the proper use of condoms, help (him or her) to cope with situations associated with drug injecting without relapsing into high-risk behaviour, or encourage entry into treatment.

Although the stereotype of an IDU might suggest an irresponsible individual with no interest in reducing the risk to self or others, the reality is usually more complicated. The overwhelming majority of IDUs strongly want to reduce their risk of HIV infection. For many, abstinence from injecting drug use is not, at least in the short term, an option, so counsellors faced with this situation need to be able to provide a range of other options and the criteria for selecting between them.

Human immunodeficiency virus testing

In the years just after the AIDS epidemic was recognized, many countries offered HIV testing, but they gave ambivalent encouragement to members of high-risk groups. In most countries, pre- and post-test counselling were stressed. Although it is questionable whether knowledge of HIV serostatus changes the behaviour of those most at risk, HIV testing in many countries has tended to become less controversial, possibly because medical treatment for HIV-infected individuals is more effective nowadays. HIV testing plays an important role in the monitoring of the epidemic, and testing data help to support the case for prevention measures.

Provision of safer injecting equipment

Increasing the availability of sterile needles and syringes is generally recognized to be a critical strategy in the control of HIV infection among IDUs. Swabs, sterile water and clean spoons also decrease the opportunity for the transmission of HIV. In some developing countries, injectable drugs are readily available and cheap but sterile needles and syringes are in very short supply, even in hospitals. Authorities are sometimes faced with extremely difficult decisions as supplying sterile needles and syringes to IDUs may be unaffordable, unacceptable or both. In this situation, encouraging a switch back to more traditional methods of consuming illicit drugs, such as smoking or snorting, may be the best long-term option but difficult to implement.

A wide range of approaches has been adopted in countries through- out the world to increase the availability of sterile needles and syringes, including dedicated needle and syringe exchanges, distribution, often through retail pharmacies, and over-the-counter sale in conventional retail outlets [2] . Research has shown that many methods are feasible, with no particular method of providing sterile needles and syringes having been demonstrated to be consistently superior, and that the choice should depend on local circumstances. Some countries continue to restrict the availability of sterile needles and syringes on the grounds that this reduces the chances of initiating a user into the practice of injecting. However, there are no data that demonstrate that the greater availability of sterile injection equipment increases the prevalence of drug injecting or numbers of IDUs. Needle and syringe exchanges initially operated independently of alcohol and drug treatment services, but in some instances they have been integrated successfully.

A range of techniques has been devised to improve the disposal rate of used injection equipment, including special plastic packs containing sterile needles and syringes and special features to retain used injection equipment. Special street bins have been put in place to reduce the irresponsible disposal of used needles and syringes. In several European countries, vending machines have been - installed in inner city areas associated with intensive illicit drug use. These machines have been made tamper-resistant and operate when a token or a coin or used injection equipment is inserted. Vending machines increase the availability of sterile injecting equipment at times and places where coverage of those especially at risk is important from a public health point of view.

Decontamination of used Injection equipment

In some countries where it has not been possible to increase the availability of sterile needles and syringes, encouraging the decontamination of used injection equipment with bleach has been useful although generally considered a second-level strategy [3] . Bleach, which destroys HIV and other hazardous microbiological agents even in relatively low concentration, deteriorates on standing or exposure to sunlight. Used injection equipment should be flushed out with water before being soaked in bleach for at least several minutes, then flushed out and then rinsed again at least twice with, preferably, sterile water. If this is not possible, the equipment should be flushed at least twice with water, twice with bleach and then twice again with water.

A range of materials is used with ordinary water, which is probably the most commonly used decontamination agent. Boiling hot water is much more likely to physically destroy HIV than cold or warm water and is therefore preferred, although cold water that has been boiled recently is acceptable. Concentrated alcohol has also been recommended and may be comparable in effectiveness to boiling water. Dilute solutions of alcohol do not effectively destroy MV. Often IDUs will use alcoholic beverages in the hope that this will decontaminate injection equipment, but this practice should not be recommended. Although high-concentration alcohol is believed to be about as effective as bleach in destroying free HIV virus, it is not as effective in destroying HIV-infected cells. Therefore, IDUs should be advised to use as high a concentration of alcohol as possible and to allow the injection equipment to remain in the solution for at least several minutes. Flushing the used needles and syringes with (preferably sterile) water before and after soaking and flushing with alcohol is recommended. Numerous other agents have been used for decontamination, although there is less information about their effectiveness. In some cities, vinegar is often used to decontaminate used injection equipment. The use of unsanitary water for flushing needles and syringes, while common, should be discouraged.

Bleach should be made readily available in small and convenient leakproof containers to increase its utilization. IDUs must be reminded that all paraphernalia used for drug injecting that could possibly be shared, including spoons, cookers, bottle tops and other, similar equipment used for mixing or drawing up solutions, needs to be decontaminated.

Provision of safer sex equipment

Although condoms and lubricants are readily available in many parts of the world, their utilization by IDUs is relatively poor [4] . Like most other heterosexual groups, IDUs do not consider themselves to be at risk of HIV transmission through intercourse. As the utilization rate of condoms by IDUs is poor, it is important that educational campaigns targeting IDUs include advice about the technique of using them which is explicit and also includes specific advice for women on the negotiation of safer sex. In hot or tropical climates, condoms deteriorate relatively rapidly, especially if exposed to direct heat.

Treatment

There is increasing evidence available to suggest that IDUs in treatment are at reduced risk of HIV infection [5, 6, 7, 8] . So far, data are available only for methadone maintenance treatment, but other modalities of treatment may also have a similar effect. Longer durations and higher doses of methadone are generally associated with a lower prevalence of HIV infection among heroin injectors.

Some countries have, for reasons of public health, encouraged HIV- infected IDUs to enter treatment. However, IDUs not infected with HIV should also be given every opportunity to remain uninfected, including by facilitating their entry into treatment. It may be important in the early phase of the epidemic to give priority to HIV-infected IDUs, but other policies may be more appropriate once substantial numbers of IDUs have become infected [9] .

Some countries have made treatment readily available to IDUs in an effort to impede the spread of HIV, while others adopt strict selection criteria and provide treatment only to the few considered most likely to benefit. In many countries, a relatively low rate of IDU participation in drug treatment has come to be accepted. In other countries, a high rate of participation has been considered important because it benefits IDUs and the general community alike. As a result of the HIV epidemic, many countries have been attempting to increase participation in treatment. Countries that wish to do this may need to increase the capacity and the attractiveness of their treatment system. It would be better to provide less intensive and less expensive forms of treatment for a large number of participants rather than more intensive and expensive treatment for the few.

Outreach

Outreach has many elements that justify thinking about it as an entity in itself [10] . Recognizing that only a minority of IDUs are in contact with traditional treatment services, outreach health and welfare staff leave their fixed locations and seek IDUs in their home territory. Outreach staff provide a range of services, including education, welfare, and the provision of sterile injection equipment, materials with which to decontaminate needles and syringes, condoms and lubricants, and they recruit IDUs into treatment.

Organizations of injecting drug users

When the epidemic of AIDS was first recognized, organizations of homosexual and bisexual males had for decades existed in many countries, which made it possible to rapidly mobilize peer counsellors to teach risk reduction. The absence of similar organizations for IDUs has not made the task of reducing risk in this population any easier [11] , [12] . Organizations of IDUs were first set up in the Netherlands and now exist in several other countries, including the United States, the United Kingdom and Australia. In some countries, organizations of IDUs provide sterile needles, syringes and bleach and collect used needles and syringes. They also offer education, advice on housing and welfare issues and advocacy and support for IDUs. In other countries, organizations of IDUs have provided an indispensable service for health authorities saddled with the problem of MV-infected IDUs knowingly exposing others to the risk of HIV infection. Organizations of IDUs have also advised health authorities planning education campaigns targeted at IDUs. Perhaps one of their most helpful roles is the support of HIV-infected IDUs. Authorities considering the establishment of organizations of IDUs need to recognize the vulnerability of these organizations, especially in their earliest years.

Research

The HIV epidemic among IDUs has irrevocably changed the nature of drug injecting everywhere in the world. Although research on IDUs has been conducted for decades, novel approaches are required [13] . Specifically, research is needed that evaluates the effectiveness not only of strategies that promote enduring abstinence but also of strategies that promote lesser goals, including a reduction in the sharing of injection equipment.

Since research on IDUs in one country or at one point in time may be only partly generalizeable to other countries or times, authorities should consider collecting their own data as an indispensable part of a comprehensive approach to the threat of HIV from injecting drug use. Health authorities will need, for example, estimates of the number of IDUs for planning prevention strategies and developing HIV treatment services. Many countries have found it helpful to monitor trends in HIV risk behaviours and relate these to demographic and seroprevalence data and prevention measures. In some countries, the existence of national data has justified implementing a range of strategies that would not have been otherwise possible.

The HIV epidemic has also exposed serious gaps in existing research on IDUs, including the lack of ethnographic studies, which can help to identify obstacles to the implementation of risk reduction strategies. Techniques for measuring behavioural change have had to be developed. In most countries, it has not been possible to even approximate the number of IDUs exposed to the risk of HIV infection, as the representativeness of samples remains problematic. The evaluation of the risks to specific populations in a country is still largely speculative.

The epidemic of HIV infection has also thrown up new issues for research. HIV infection in IDUs has been associated with increased risk of bacterial pneumonias and tuberculosis, which are not part of the conventional definition of AIDS [14] , [15] , [16] . How might HIV infection affect the spread of these serious illnesses in different countries? How many needles and syringes need to be made available to minimize the spread? What are the best methods of making injection equipment available? How can political commitments to support HIV prevention be developed in time? The factors responsible for IDUs switching from parenteral to non-parenteral methods of consuming drugs and measures that will encourage IDUs to utilize non -parenteral forms of administration are areas that are assuming importance.

The HIV epidemic has highlighted the need to increase the effectiveness and reduce the cost of drug treatment. In developing countries where methadone may be unaffordable but where opium is cheap, tincture of opium as a form of substitution therapy should be evaluated. The risk of HIV transmission associated with the intravenous use of cocaine has highlighted the need for improved treatment interventions for cocaine users. Preventing the further spread of HIV infection in developing countries is an entirely new field for research.

Managing high-risk injecting drug users who knowingly infect others

In many countries, a few IDUs have caused concern because they knowingly place others at risk. There are a number of options for managing these individuals, although all are less than ideal. Some have been legally confined to psychiatric hospitals or other institutions for a period. Others have been rehoused in remote places although not legally confined against their will. Organizations of IDUs have proved very helpful in attempts to stabilize such individuals. Public authorities have often invested considerable resources and time in attempting to develop a satisfactory solution. However, the claims on resources have to be balanced against the many other competing claims of the HIV epidemic. Ultimately, the likelihood of success in this area must be realistically compared with the likelihood of success in other areas related to controlling the epidemic.

Prisons

The range of options for checking the spread of HIV infection in prisons was canvassed in a meeting convened by the World Health Organization, which recommended that, wherever possible, strategies being used in the general community should be considered for correctional facilities. Some people spend up to 70 per cent of their careers as IDUs in prison. A substantial proportion of male and female prisoners have been convicted of other offences but are also IDUs. Drugs or injection equipment somehow seem to find their way into prisons despite Draconian penalties and stringent attempts at detection. There, the limited supplies of injection equipment are generally reused to a far greater extent than in the community [17] , [18] , [19] , [20] .

In most countries, prisoners are not given bleach to decontaminate used injection equipment, because this would appear to condone illicit drug use in prisons. Sterile injection equipment is not provided in prisons anywhere in the world, even on a strict one -for -one basis (which would not increase availability), although such a practice is being considered in some countries. Prison authorities fear that some prisoners would use needles and syringes filled with blood from HIV-infected persons as weapons against prison officers. Condoms are being provided to male prisoners in a few countries. In recent years, authorities in some countries have expanded drug treatment services and permitted methadone treatment services to be established within prisons. Diverting more IDUs convicted only of drug-related offences from prisons to non-custodial forms of sentencing would decrease the population exposed to the risk of HIV infection in prison.

Prison services often see IDUs who have had no previous contact with health or welfare services and only limited exposure to education about HIV infection. It is not known whether IDUs in prison are exposed to greater risk of HIV infection than IDUs outside prison. Limited research on this question is available [17-20] . Data from different countries on HIV transmission within prisons may be of limited generalize- ability because of large differences in the administration of prisons. However, data from Europe and Australia suggest that over 50 per cent of IDUs continue to inject and share in prison, with perhaps one IDU male prisoner in 20 engaging in unprotected anal intercourse. The wide dispersal of prisoners after they have been discharged suggests that a small group of infected prisoners may have more serious public health consequences than a small group of infected IDUs in the community.

Prison authorities are faced with the difficult choice between strengthening attempts to stem the supply of illicit drugs in prison or reducing the hazardousness of high-risk behaviours. Decreasing the supply of drugs in prison may diminish the frequency of episodes of high-risk behaviour but inadvertently increase the likelihood that individual episodes of risk behaviour will result in HIV transmission.

Conclusion

The multiplicity of potential interventions, community sensitivities about illicit behaviours, the conflict between measures to reduce the spread of HIV and policies to reduce supply, and the difficulties of evaluating a number of preventive measures implemented simultaneously have prevented or delayed the introduction of many of these strategies in most countries. The severity of the health, social and economic consequences in communities where the spread of HIV among IDUs is poorly controlled, the continuing spread of HIV in IDU populations, the high (but declining) levels of risk behaviour and the high seroprevalence of other blood- borne infections suggest the urgent need for risk assessment

and, where required, a vigorous response to the IDU component of the HIV epidemic.

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