Critical issues regarding AIDS among injecting drug users

Sections

ABSTRACT
Introduction
Political denial and compartmentalization of the problem
Stereotypes, policies and AIDS prevention
Behaviour of IDUs in response to AIDS
Conditions that foster the large-scale injection of illicit drugs
The role of drug transport patterns
Individual transitions between non-injected and injected drug use
Prisons as a place for HIV prevention
Summary

Details

Author: D.C. DES JARLAIS , S.R. FRIEDMANN
Pages: 61 to 75
Creation Date: 1993/01/01

Critical issues regarding AIDS among injecting drug users*

D.C. DES JARLAIS Beth Israel Medical Center, New York, N.Y., United States
S.R. FRIEDMANN National Development and Research Institute, Inc.; New York, New York, United States of America

ABSTRACT

The paper identifies and reviews some critical issues in the field of human immunodeficiency virus (HIV) transmission among intravenous drug users. First, it discusses political denial and compartmentalization of the problem, giving an example from the United States that illustrates the lack of a coherent national strategy. It then reviews the role that stereotypes play in policy-making and points out that behaviour change can be considerable, giving details of successful safer injection programmes. The conditions that foster injection as a mode of ingesting drugs are reviewed, as is the role of drug transshipment patterns, particularly as a possible conduit of HIV. Finally, the role of prisons as places for the spread of HIV, and therefore for its prevention, is discussed.

*The authors wish to thank R. W. Burnham, United Nations International Drug Control Programme, for his contribution to this article, and Thomas P. Ward for editorial assistance.

Introduction

It has now been over a decade since acquired immunodeficiency syndrome (AEDS) was first reported in injecting drug users (IDUs). During the last 10 years there has been considerable research into how to reduce HIV transmission both among IDUs and from IDUs to their sexual partners and their children. Moreover, many nations have undertaken substantial programmes to reduce this transmission, with some exemplary local successes in slowing or preventing the spread of HIV.

Despite these efforts, however, the situation worldwide is worse today than it was a decade ago. HIV infection among IDUs is now a threat to the public health in over 50 different countries. HIV has spread very rapidly among IDUs in both developed and developing countries. (See Des Jarlais and others [1] , Stimson [2] and Mann, Tarantola and Netter [3] for recent reviews of the epidemiology of AIDS among IDUs.)

In this paper, some critical issues in the field of HIV transmission among IDUs are identified and reviewed. Areas in which better information is needed before effective interventions can be designed or implemented are discussed. Policy concerns are a good place to start, because difficulties in the policy area have often hindered the utilization of available scientific knowledge about the most effective means of preventing HIV transmission among IDUs.

Political denial and compartmentalization of the problem

Despite the high rates of HIV infection and cases of AIDS among IDUs in different countries, many political leaders -either, deny the problem's seriousness or compartmentalize it, as if it were separate from the larger problem of illicit psychoactive drug use.

To cite only one example, the United States clearly has the largest problem of HIV infection among IDUs. There are an I estimated 1.3 million persons who inject illicit drugs in the United States, and their HIV infection rate is estimated to be between 25 and 35 per cent, which means there are 300,000-400,000 HIV-infected IDUs. Despite the enormity of the problem, however, the official statement of the national plan for combating illicit drug use, as developed by the Office, of National Drug Control Policy, hardly mentions AIDS or HIV infection. In the 1991 national plan document, there were only three paragraphs devoted to AIDS in a lengthy text, and AIDS was treated simply as one more reason why people should not inject illicit drugs. Moreover, there was no mention of any need for special programmes to prevent HIV infection among IDUs, their sexual partners and their children. There was also no mention of the immediate need to provide vastly improved health care to IDUs, their sexual partners or children already suffering from HIV-related illnesses.

This lack of attention to AIDS in what was, supposed to be a national plan for addressing illicit drug use prompted a highly critical response from the United States National Commission on AIDS: "The Federal Government must recognize that HIV ... is one of the issues of paramount concern within the 'war on drugs" [4] . Yet even today, despite the sheer size of the problem in the United States, the amount of money that has been spent collecting information about separate aspects of the problem, estimated to be over US$ 100 million, and the media attention given to the topic (syringe exchanges, in particular, have been extensively covered by the media), the United States still does not have a coherent national strategy for addressing the many interrelated problems caused by HIV infection among IDUs. This lack of a consistent national policy in the United States has been the result of fundamental differences over what should be done, including strong disagreements between different branches and levels of Government, rather than of a simple lack of attention to the problem. Disagreement has been particularly strong over safer injection programmes, such as syringe exchanges, which would reduce HIV transmission without necessarily reducing illicit drug injection per se.

Other countries have also experienced major difficulties in developing and implementing plans for addressing HIV infection among IDUs. In some countries, greater consideration has been given to the problem of AIDS among IDUs, and because of the high fatality rate associated with HIV infection and because HIV infection is often transmitted from IDUs to their sexual partners and potential children, the prevention of AIDS is given priority over stopping illicit drug injection as such. While such prioritizing can be justified on a public health basis, it implies irreconcilable conflict between reducing AIDS and reducing illicit drug injection and thus limits the development of programmes that might simultaneously achieve both aims. Of course there will always be a need to set priorities among policy objectives, in order to allocate scarce resources. Nonetheless, the intertwined nature of illicit drug injection and HIV infection, and related diseases such as tuberculosis, will require that policies be coordinated on a worldwide basis. If there is no such coordination, opportunities to achieve complementary goals with respect to HIV prevention and the reduction of illicit drug injection will be overlooked. It is beyond the scope of this paper to enumerate and analyse the many problems that various countries have encountered in coordinating policies with respect to HIV and injecting drug use. The authors' experience shows, however, that one of the main problems in developing policy arises from the misleading stereotypes that some policy makers have about IDUs.

Stereotypes, policies and AIDS prevention

In many countries, policies about illicit drug use are formulated without any input from active, or even former, IDUs. Despite the technical information drug users might have to offer, they are usually not considered legitimate participants in policy decisions about illicit drug use. Technical expertise is usually provided only by law-enforcement officials and/or officials involved in drug abuse treatment. From the perspective of most law - enforcement officials, drug distributors and often drug users themselves are considered to be immoral and antisocial. They not only break the laws governing the possession and use of banned substances but also frequently break other laws in order to maintain their drug-distribution business or to obtain money for the purchase of drugs. From the perspective of many drug abuse treatment officials, illicit drug users are pathologically driven to continue using their drugs and hence are not capable of making rational choices about their own drug-using behaviour.

Obviously, neither of these perspectives would lead to the expectation of much behaviour change from drug users faced by HIV infection and AIDS. From the law-enforcement perspective, most drug users are seen as too focused on their immediate pleasure to be concerned about their own health or that of anyone else. From the drug-treatment perspective, the power of the addiction is viewed as preventing the drug user from changing his or her behaviour unless the addiction process itself can first be stopped. Given these underlying assumptions, it is not surprising that in many countries, both law enforcement officials and drug abuse treatment officials have repeatedly predicted that AIDS prevention programmes for IDUs would not be effective. Many have even predicted that some types of AIDS prevention programmes would not only fail to reduce HIV transmission but would also undermine law-enforcement activities and the motivation of drug users to enter treatment programmes [5] .

Behaviour of IDUs in response to AIDS

The evidence shows, however, that IDUs have not only changed their behaviour in response to AIDS but have also behaved altruistically by encouraging others to change behaviour and, even among those IDUs who have learned that they themselves are already HIV-infected, by reducing the chances that they might transmit HIV to others. Almost all studies of AIDS prevention programmes have shown that the majority of subjects changed their behaviour in order to reduce their chances of contracting AIDS (see Des Jarlais and Friedman [6] for a review). Moreover, several studies have shown some degree of AIDS risk reduction even in the absence of any formal prevention programme [7] , [8] In general, the more effective programmes are those that provide not only accurate information about AIDS and HIV infection but also the actual means for behaviour change (whether drug abuse treatment for those who choose to stop or reduce their drug use, or means for safer injection for those continuing to inject), as well as those programmes that facilitate the process by which IDUs influence one another to curtail risky behaviours.

Changing injection practices, especially obtaining sterile injection equipment or no longer injecting with equipment used by others, has been the dominant form of AIDS risk reduction among IDUs. Reducing drug injection as such and changing sexual behaviour have also occurred to some extent, but clearly not as frequently as practising safer injection.

Indeed, one of the products of social interactions among IDUs themselves in recent years has been the emergence of a new social norm in many places against the sharing of injection equipment. Where sharing equipment was once considered to be supportive, friendly behaviour, it is now seen as dangerous and potentially hostile.

Another of the findings that has consistently emerged from studies of AIDS prevention programmes aimed at IDUs has been the complementarity of safer injection programmes and drug abuse treatment programmes. Safer injection programmes typically provide legal access to sterile injection equipment, either through unrestricted over-the-counter sales of injection equipment or through syringe-exchange programmes, in which IDUs exchange their used injection equipment for new, sterile equipment. (The used equipment is then safely disposed of by the syringe-exchange staff.) Some safer injection programmes, often those in jurisdictions that do not permit legal access to injection equipment, provide bleach or other means for disinfecting used injection equipment. When the safer injection programmes were first begun, many drug- treatment officials were concerned that the programmes would undermine the incentive for IDUs to enter treatment programmes. In fact, the safer injection programmes have often become an important source of referral by which IDUs have entered treatment. Indeed, in some locations, the safer injection programmes have become the leading local source of referrals into drug abuse treatment [9] ,[10] . The non-judgemental contact between IDUs and the staff of safer injection programmes tends to engender trust between the two groups, which often results in the IDUs becoming more concerned about health, and hence more willing to enter drug abuse treatment programmes.

Few random -assignment clinical trials have been conducted to assess the effect of AIDS prevention programmes among IDUs on the actual transmission of HIV. A true random -assignment clinical trial study would require using communities as the unit of analysis and therefore would he difficult from a logistical standpoint and from a political standpoint (communities would have to be willing to accept random assignment into different conditions). It would also be very expensive, probably costing tens of millions of United States dollars per year for five or more years. Even without a true random-assignment clinical trial, however, there is already substantial evidence that the behaviour changes reported by IDUs participating in prevention programmes have substantially slowed the spread of HIV. MV infection levels (seroprevalence) stabilized in many cities following large-scale behaviour change among IDUs, including in Amsterdam [11] , Stockholm[12] ,[13] Vienna [14] , San Francisco [15] , Geneva [16] , Bangkok [17] ,[18] and New York [18] . This stabilization of HIV seraprevalence has occurred at very different levels, from 2 per cent in Skane, Sweden [13] to 50 per cent in New York City [18] , and in some cases represents actual reductions in the rates of new HIV infections among

IDUs in the area. There are also self-report validation studies from Bangkok [19] and Rio de Janeiro [20] , corroborating that IDUs who report that they changed their behaviour were indeed significantly less likely to be infected with HIV. Finally, there are studies showing that behaviour change by IDUs was followed by lower rates of new hepatitis B infections among IDUs in Amsterdam [11] and in Tacoma, Washington [21] . (Hepatitis B spreads by the same modes of transmission as HIV but is much more efficiently transmitted.)

In several cities, such as Glasgow, Sydney, Lund and Tacoma, there was awareness of the potential for an epidemic based on what had already happened elsewhere, so prevention programmes were initiated before large-scale introduction of HIV into the local community [22] . As a result of these timely measures, very high percentages (80 per cent or more) of drug injectors changed their behaviour to reduce the chances of exposure to AIDS, and HIV seroprevalence has remained at less than 5 per cent for four or more years. In these cities, then, it is possible to think in terms of successful prevention of HIV epidemics among IDUs.

Nonetheless, despite this convincing evidence showing behaviour change on a large scale among IDUs in many different countries, it remains difficult for many policy makers to think of IDUs as capable not only of changing their own behaviour but also of influencing each other to reduce the risks of HIV transmission. Input from drug users into HIV prevention policy design and implementation could do much to change current stereotypes of IDUs. In both Australia and the Netherlands, the active participation of IDUs in official AIDS prevention efforts, in part initiated by the earlier volunteer efforts and advocacy of drug users' own organizations, is now generally recognized, even by those who were initially sceptical, as having been extremely beneficial to those efforts [23] . Nonetheless, relatively few policy makers in other countries are willing to grant any such legitimacy to views expressed by active drug users. In the face of such prejudices, research data may be the best substitute.

The positive responses of IDUs to current forms of AIDS prevention, i.e. safer injection programmes and drug abuse treatment, indicate that the immediate problem in preventing HIV infection among IDUs is primarily one of developing the political will and finding the resources necessary to implement the programmes on a large scale in many different countries.

Long-term public health control of HIV infection among IDUs will, however, require that more fundamental issues be addressed. Long-term control of HIV infection will require success in reducing both demand and supply to reduce the number of persons who are injecting illicit drugs. As long as large numbers of persons are injecting illicit drugs, controlling the transmission of HIV and other viruses will remain problematic. This is particularly true where HIV is already established at a high background seroprevalence rate among IUDs; in such areas, a relatively small extent of sharing of injection equipment can lead to HIV transmission [24] .

In the rest of this paper, some of these more fundamental questions will be outlined, and the policy implications will be extended from programmes aimed primarily at preventing RIV transmission to broader concerns of reducing drug supply and demand.

Conditions that foster the large-scale injection of illicit drugs

Before the 1970s, the injection of illicit psychoactive drugs was considered to be a large-scale problem only in the United States [25] . In the 1970s, however, illicit drug injection spread rapidly in many countries of western Europe. Moreover, during the 1970s and 1980s it also spread rapidly in several developing countries, particularly in Asia and South America. There is now concern that illicit drug injection may expand rapidly across eastern Europe. Injecting drug use has occurred not only in widely varying cultures, from Christian to Muslim to Buddhist, but also in different social classes, from university students to urban and rural labourers. There is as yet no good explanation for the increase in illicit drug injection over the last two decades. It is possible that rapid cultural changes and socioeconomic dislocations, including those caused by rapid economic growth, produce the preconditions for widespread illicit drug injection by creating large groups -of persons willing to use illicit drugs and smaller, but still sizeable, groups willing to engage in distributing the drugs. To the extent that such cultural and socioeconomic dislocations are an almost inevitable by -product of economic development under current socioeconomic conditions, it will be very difficult to restrain the further spread of illicit drug injection. Better knowledge of the exact relation- ships between such dislocations and illicit drug injection might, however, permit the better focusing of efforts to reduce both supply and demand for drugs, and to reduce the likelihood that such dislocations will lead to the more negative consequences of large-scale illicit drug injection.

It is also possible that the injection of illicit drugs should simply be seen as an irreversible technological improvement over drug administration routes that do not involve injecting. The injection of psychoactive drugs is a highly cost-efficient method of drug administration. It provides rapid delivery of the drug to the brain, causing an intense effect, and almost all of the drug is used when it is injected. The smoking of drugs such as heroin and cocaine also provides rapid delivery to the brain and an intense drug effect, but much of the drug is lost during smoking because the user cannot inhale all of the fumes. Of course, it should be noted that the method of administering a drug by injection becomes particularly attractive only under conditions in which drugs are very scarce and/or very expensive and that previous attempts to reduce supply inadvertently gave some habitual users the incentive to begin injecting. To the extent that the injection of illicit psychoactive drugs is an irreversible technological improvement, there may be little that can be done to prevent the further diffusion of the technique. More study is needed to identify the conditions under which injection as a technological innovation is most likely to be adopted and the interventions that could reduce the likelihood of such conditions developing. Sentinel surveillance systems might be instituted, for instance, that would facilitate more rapid implementation of programmes to limit viral transmission among populations adopting the practice of illicit drug injection.

It may also be the case that there are no general explanations for the spread of illicit drug injection over the last two decades and that explanations need to be sought in local conditions. The suppression of illicit opium smoking was followed by the development of heroin injection in both New York City[26] ,[27] and Bangkok [28] . There are not enough data to suggest that policies framed to facilitate non-injected forms of drug use will prevent illicit drug injection and/or the spread of HIV. However, it is suggested that policy makers should conduct cost- benefit analyses before undertaking to suppress non-injected modes of illicit drug use. It would be important for such analyses to consider what will happen to persons who are dependent on illicit drugs taken in non-injected forms. Will they become a ready market for injectable drugs? If a policy decision is made to suppress the use of non-injected illicit drugs, it would be important to plan and provide for drug abuse treatment, as well as for other means of harm reduction, for persons who are dependent on those non-injected forms.

The role of drug transport patterns

One aspect of modern drug-distribution systems that deserves further study is the role of transport in the spread of drug injection and HIV.

Both drug injection and HIV infection among IDUs appear to follow drug transit routes [1] . There is, for example, a path of high HIV infection rates along the drug trucking routes leading south from the Amazon region to the coastal ports of Rio de Janeiro and Santos in Brazil. There are also high HIV infection rates among IDUs along the land shipment routes out of the Golden Triangle, south to Bangkok, west to northern India and east to Hong Kong. There is a similar path of high HIV infection rates among IDUs in southern Europe, across Switzerland, northern Italy, southern France and Spain.

The economics of heroin and cocaine production make it only marginally more expensive to produce extra quantities of these drugs to build up and supply local markets along drug transit routes. That is, it costs very little to produce the incremental drug, and the mechanisms for transporting the drug are already in place.

Why and how HIV infection appears to spread along drug transit routes remains to be determined. One factor may be that, contrary to popular belief, many IDUs do travel outside of their home cities. A World Health Organization multi-site study of IDUs in 13 cities found that approximately one quarter of the subjects had travelled and injected drugs outside their home cities in the previous two years [29] . Whether IDUs travel as part of employment in drug transport or simply happen to travel along the same routes has not been determined.

One of the disturbing aspects of drug transport with modern transportation systems is the ease with which the routes can be altered. Particularly with air transportation, routes no longer need to be direct and can be changed with relative ease, which often occurs in response to intensified law-enforcement activities. As law enforcement raises the costs of using a particular route, the distributors will seek new routes. This occurred in the United States when the South Florida Task Force mounted somewhat successful operations against cocaine smuggling into southern Florida. In response, distributors simply changed routes and began flying the drugs directly into southern Georgia. Rural southern Georgia soon developed its own large-scale illicit drug problem, and HIV spread among drug injectors and persons exchanging sex for drugs.

This example is not meant to imply that law-enforcement activities against drug transport should be scaled back in order to limit the geographic spread of HIV. Such a scaling back could increase the distribution of illicit drugs and increase opportunities for the transmission of HIV in connection with drug use. It does suggest, however, that there needs to be good cooperation between law enforcement and health officials so that as new routes develop, demand reduction and HIV prevention activities can be implemented before high rates of HIV infection develop among the IDUs along them.

Individual transitions between non-injected and injected drug use

The need for better information on group transitions from non-injecting drug use to injecting drug use was noted above. There is also a great need for better information about individual transitions from non-injecting drug use to injecting drug use [30] ,[31] . Most persons who inject heroin and cocaine go through a period of non-injecting use, either smoking or intranasal use, before they start injecting. The traditional barriers to starting to inject drugs were a fear of needles and the concern that injecting would lead to loss of control over drug use to the point of outright addiction. Concern about AIDS may have recently become another barrier to starting to inject, although this has not been well documented. A number of factors have been associated with the transition from non-injecting to injecting drug use, including curiosity about the better high, friends or relatives who inject and serve as role models (and teach how to inject), and high levels of non-injecting drug use (injecting provides a much more cost-efficient drug effect).

Recently, however, there have been reports of the increased use of non-injecting drugs in New York City [30] and in London [31] , although the reasons for the increases have not yet been determined. One factor that appears to be associated with non-injecting drug use is the high purity and low price of the illicit heroin that has recently come on the market. The high purity and low price serve to partially offset the economic advantages of injection as a route of administration. More effective efforts to reduce supply would probably lead to less pure, more expensive drugs and, if the historical precedent is followed again, might lead to an increase in drug injection, particularly among persons who have become addicted through their non-injected drug use. Whether or not concern about HIV transmission should become a rationale for not intensifying supply-reduction efforts, it is clear that any such efforts should be accompanied by more drug abuse treatment programmes and safer injection programmes. Additional study will be needed to determine which types of drug treatment programmes and which types of safer injection programmes would be the most effective for relatively new drug injectors.

Prisons as a place for HIV prevention

In many countries, large numbers of IDUs are incarcerated. This presents both opportunities and problems for HIV prevention efforts. Prisons can be used as sites for drug abuse treatment: both therapeutic -community treatment and methadone maintenance treatment have been provided in prison settings [4] . The lack of well-developed procedures for transition from the prison environment back to the community points up a serious limitation of current prison-based treatment programmes, but this should not be seen as an insurmountable obstacle.

Prisons with large numbers of IDUs also provide a good site for education about AIDS. Again, there is the problem of the transition from the prison back to the community, but certainly large numbers of IDUs can be reached with information about AIDS while they are held in prison systems. In areas with high HIV seroprevalence among IDUs, prisons are also an important place for delivering medical care to those suffering from HIV-related diseases.

These opportunities to offer drug abuse treatment, AIDS education and medical care for HIV -related diseases to IDUs are important because the clandestine lifestyle that many IDUs led in the community, which is a rational response to the stigmatization many of them encounter in mainstream society, rendered them "invisible" to the health-care system. Moreover, because they understandably fear being identified as illicit drug injectors, many IDUs extend their fear and distrust of authority to public-health authorities. Indeed, many IDUs continue to conceal their identities even though they have been aware throughout the HIV epidemic of their high risk of exposure.

However, the opportunities of using prisons as places for addressing HIV among IDUs are probably outweighed by the difficulties that injecting drug use and HIV infection create for prison administrators and for the prisoners themselves. The inherently non -therapeutic environment of prisons serves to limit the effectiveness of both drug abuse treatment and AIDS education provided within prisons. Moreover, maintaining confidentiality with respect to previous drug use and current HIV infection status can be difficult enough in many normal health-care settings, and it is particularly difficult in prisons. Concern about potential HIV transmission from inmates to staff may create considerable problems for staff morale. Fortunately, most of the concern about inmate-to-staff transmission is unrealistic and can be assuaged by proper staff education. There is, however, a realistic potential for the transmission of tuberculosis from inmates to staff, and tuberculosis could become a real danger in many of the prisons that now have high HIV infection rates among the inmates. While many persons with HIV -related illnesses may be available for treatment in prisons to a greater extent than they would have been in the outside world, prison medical staff typically do not have the resources for meeting current standards of care. Indeed, a recent cross-national survey of prison policies and practices with respect to HIV found that very few systems met currently accepted standards for dealing with HIV infection among prisoners and even fewer used the opportunities for implementing HIV prevention measures or for treating HIV-related diseases [32] . Clearly, the prevention of tuberculosis and MV among inmates is not only a matter of ethics and public health, but it is also necessary for effective and humane prison administration.

The most difficult problem with respect to HIV and prisons, however, is preventing HIV transmission among inmates while they are in the facility. Of course, the activities that transmit HIV, i.e. unprotected sexual intercourse and the sharing of drug injection equipment, are officially banned in prisons. Nonetheless, even though it is unrealistic to expect prisons, particularly those that are understaffed and overcrowded and that house large numbers of persons with drug abuse problems, to be completely free of these activities, it is extremely embarrassing politically for prison officials to publicly admit that these activities do in fact occur. Such denial has been one of the reasons why the distribution of condoms, bleach and sterile injection equipment has been limited within prisons. In any event, the multiple difficulties associated with trying to prevent HIV transmission in prisons are sufficiently daunting that some authorities have suggested that more alternatives to incarceration should be developed for persons likely to engage in high-risk behaviour, particularly IDUs [33] .

The many problems created by HIV infection among inmates demonstrate the interdependence of the health-care system and the law- enforcement system. If the public-health system fails to prevent HIV infection among IDUs prior to incarceration, this failure in turn creates massive additional difficulties for the correctional system. The correctional system as presently organized is not well-suited to compensate for the failure of the public-health system to prevent HIV infection.

Summary

After 10 years of experience with HIV infection among IUDs, much is known about what can be done immediately to reduce HIV transmission by the sharing of drug injection equipment. Both safer injection programmes and drug abuse treatment can reduce such transmission, and these activities should be considered as complementary rather than competing. Many of the problems encountered in implementing them stem from the behaviour of political leaders rather than from the behaviour of IDUs. Indeed, despite the massive and consistent evidence to the contrary, many political leaders still formulate policies as if IDUs were incapable of changing their behaviour.

The long-term international control of HIV infection among IDUs will require addressing two issues: the continuing injection of illicit drugs where the practice has become established and the spread of illicit drug injection to new areas. While there is still much to be learned about methods for simultaneously controlling illicit drug injection and HIV transmission among IDUs, it does appear that the coordination of programmes for supply reduction, demand reduction and HIV prevention would greatly increase the chances of each for success.

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