Drug injecting and HIV infection among the population of drug abusers in Asia

Sections

ABSTRACT
Introduction
Drug injecting among the population of drug abusers
South-West Asia and South Asia
South -East Asia and East Asia
HIV infection among injecting drug users
Concluding remarks

Details

Author: V. POSHYACHINDA
Pages: 77 to 90
Creation Date: 1993/01/01

Drug injecting and HIV infection among the population of drug abusers in Asia

V. POSHYACHINDA
Director, Institute of Health Research, Chulalongkorn University, Bangkok

ABSTRACT

Opium has been produced and consumed since the nineteenth century in the areas of Asia currently referred to as the Golden Crescent and the Golden Triangle. In the 1970s and 1980s, most countries from Afghanistan to Japan experienced a heroin epidemic of varying degrees of severity. Opium and heroin abuse appeared to be more severe in countries and areas where those drugs were produced, an exception being Hong Kong, which has had a large population of heroin abusers for more than two decades. Drug injecting was far more common in countries of the Golden Triangle than in those of the Golden Crescent. In Myanmar and Thailand, for example, up to 90 per cent of chronic heroin abusers practised intravenous injection, which appeared to spread to heroin abusers in nearby territories such as the State of Manipur in India, Yunnan province in China, as well as Malaysia and Vietnam. Amphetamine abuse was more frequent in Japan and the Republic of Korea for a number of years, while illicit production and consumption in the Philippines have recently shown significant increases. The injection of amphetamines was common only in the Republic of Korea .The prevalence of injecting among institutionalized methamphetamine abusers was reported at about 90 per cent. Most countries in Asia first reported cases of infection with the human immunodeficiency virus (HIV) in the mid-1980s. An extremely rapid spread of the epidemic and high prevalence, at rates of from 30 to 90 per cent, of HIV infection among the sample of intravenous heroin abusers were observed in a few countries with a high prevalence of intravenous injecting, such as India (in the State of Manipur), Myanmar and Thailand. The rest had either few reported cases or none at all, even though needle -sharing was found to be common. Great caution should be exercised in interpreting prevalence because of vast differences in methods of assessment. Given the vulnerability of intravenous drug abusers to rapid transmission of HIV infection, the prevention of drug injecting is of paramount importance in arresting the spread of the epidemic. Efforts to contain drug abuse, though difficult, are a principal means of achieving that end.

Introduction

The present paper describes the situation with regard to drug injecting and HIV infection among the population of drug abusers in Asian countries from Afghanistan in the south -west to Japan in the east. The information and statistics presented were selected with a view to illustrating the pattern of diffusion or expansion of drug injecting or HIV infection among the population of drug abusers.

The extensive abuse of opiates in Asian countries has acquired a notoriety almost equal to that of opium and heroin production in the countries of the Golden Crescent and the Golden Triangle. Increased supplies from those two areas during the 1980s led to a sharp rise in illicit global narcotics consumption. In retrospect, however, the production and consumption of opium has had a long history in the regions of Asia concerned.

Drug injecting among the population of drug abusers

The history of drug abuse in Asia has been marked by epidemic outbreaks of parenteral morphine injection. In 1908, the Royal Gazette of Thailand, an official law journal, recorded an epidemic of parenteral morphine injection among the population of opium abusers in a town in southern Thailand [ 1] . During the 1950s, morphine dens proliferated in the poor sections of Singapore [ 2] , in association with widespread parenteral injection. After the Second World War, an epidemic of amphetamine abuse involving large numbers of injectors ( [ 3] , pp. 4-5) struck Japan in the late 1940s. Such outbreaks of drug abuse in the past aroused deep anxiety among the authorities and within the general public.

South-West Asia and South Asia

The seat of the Golden Crescent lies in South-West Asia and South Asia, including districts in the North -west Frontier Province of Pakistan, the adjacent Badakhshan area of Afghanistan and the Baluchistan area of the Islamic Republic of Iran. The area has been the scene of traditional opium poppy cultivation since the nineteenth century. The opium produced was for indigenous use, including smoking and eating, in practically all countries in the region. The traditional pattern of indigenous opium use remained fairly untouched by drug injecting throughout the 1960s [ 4] , [ 5] , [ 6] .

Under differing circumstances, heroin began to infiltrate the indigenous opium -using population of each country during the 1970s. By the 1980s, most countries in the region had become aware of the rising epidemic of heroin dependence, and there was a great need for systematic national assessments of the extent and nature of heroin abuse. The indirect indicators mentioned below were quite sufficient, however, to confirm the existence of the heroin epidemic. Law enforcement controls, which often lagged years behind the emergence of national awareness, began to result in substantial heroin seizures annually in countries where they had never before occurred, for example, in India [ 7] and Sri Lanka [ 8] . There were increasing numbers of offences against narcotics control laws [ 9] . Similarly, hospital statistics showed rising trends in the number of heroin users seeking treatment, although the figures involved were relatively small in absolute terms [ 10] , [ 11] .

The common method of heroin use in most areas appeared to follow indigenous practices, that is, smoking and a method of fume-inhaling known as "chasing the dragon" ( [ 12] , [ 13] ; [ 14] , p. 1). Drug injecting in countries of the region varied considerably among the populations studied. Epidemiological studies in Nepal showed that heroin abuse started in the early 1970s, and reached epidemic levels in 1982 and 1983. More than 90 per cent of heroin abusers were male, and a 37.0 per cent prevalence of, intravenous injecting was reported in 1989 [ 13] . There was an injecting prevalence of about 11 per cent among the small number of heroin dependents in the drug addiction treatment programme of the All- India Institute of Medical Science between 1981 and 1984 [ 15] . In 1991, the number of intravenous heroin abusers alone in the State of Manipur in north-eastern India on the border with Myanmar was estimated at about 20,000 [ 16] . An extremely low lifetime drug-injecting prevalence of between 0 and 8.8 per cent was recorded in a report on cases of treatment for drug abuse at Gale, Sri Lanka, between 1983 and 1988, and in a survey, conducted by the National Dangerous Drug Control Board, of 936 heroin users in three major affected cities in Sri Lanka [ 14] . Most studies of drug abusers in countries with low injecting prevalence often described the prevalence as "low or rare", without reporting the frequency.

Table I shows the relative extent of drug injecting among the population of drug abusers in countries of South-West Asia and South Asia.

Table 1. Estimated prevalence of drug injecting among the population of heroin abusers in countries of South-West Asia and South Asia

Country

Drug injecting prevalence(Percentage or frequency of abuse)

Afghanistan
..
Bangladesh
Rare
India
10-90
Nepal
35
Pakistan
Rare
Sri Lanka
less than 10

South -East Asia and East Asia

South-East Asia and East Asia encompass the current major sources of illicit opiate production in the Golden Triangle.

Most countries and territories of the region have been affected by the heroin epidemic of the recent past. Heroin use first started in Hong Kong around the 1920s, when the supply in fact came first from Europe [ 17] . A heroin epidemic struck Japan during the 1950s, as reflected in the annual statistics on offences against the narcotic laws ( [ 3] , p. 3). A wave of heroin epidemics followed, in the 1960s in Thailand [ 18] and the Philippines [ 19] , and in the 1970s in Myanmar [ 20] , [ 21] , Malaysia [ 22] , Indonesia [23, 24] and Singapore [ 25] . Practically no country in the region today can claim to be completely free from some degree of illicit narcotics consumption. In terms of drug injecting, however, the pattern has been quite different from one country to another.

Countries around the Golden Triangle in South-East Asia appear to have had a high prevalence of intravenous drug injecting. Between May and December 1990, drug dependents in the Treatment and Research Unit of the Yangon Psychiatric Hospital in Myanmar had an intravenous heroin injecting prevalence of about 87 per cent [ 26] . The 1989 heroin- dependent population under treatment in Thailand also included about 87 per cent of injecting heroin abusers. However, among new cases the percentage was only 71.3 per cent [ 27] . At the beginning of 1990, the Centre for Treatment at Ho Chi Minh City in Viet Nam treated 1,298 cases, 91.9 per cent of which were male. The principal substance used was opium, and the prevalence of intravenous injecting was high, at about 97 per cent. Of those cases, 64.2 per cent were addicted before 1975 [ 28] . Malaysia had a fairly large population of heroin abusers that preferred inhalation by the method known as "chasing the dragon". However, from 20 to 40 per cent of either new or re-entry cases of Malaysian heroin dependents who crossed the border into Thailand for treatment reported injecting heroin intravenously [ 29] .

Although Indonesia and the Philippines suffered a heroin epidemic in the 1970s, they never subsequently experienced heroin abuse to any significant extent. The number of -opiate dependents who entered treatment programmes in Indonesia from 1986 to 1989 varied between only 4 and 33 cases [ 30] . In the late 1980s, the Philippines were suffering from the rapidly rising number of abusers of stimulants, in particular amphetamines and. ephedrine hydrochloride, which were consumed by eating or fume inhaling with apparently little opiate abuse [ 31] , [ 32] . The prevalence of intravenous injecting has been reported at 3.6 per cent in the Philippines since 1978 [ 33] , and presumably remains low. Between 1986 and 1990, the annual statistics of heroin-using drug offenders still ranged from 3,000 to 5,500 in Singapore, with the prevalence of intra- venous injecting in that population well below I per cent [ 34] .

Between 1986 and 1991, the number of annual registered persons reported by the Hong Kong Central Registry of Drug Abuse was 15,000 to 17,500 cases. Those new to the Registry ranged from only 2,000 to 2,500 cases. The prevalence of intravenous heroin injecting varied from 20 to 40 per cent for newly registered cases, and from 55 to 65 per cent for re-entry cases [ 35] .

Taiwan Province of China had small numbers of injecting opiate dependents. Opium, morphine and heroin were substances of abuse reported by drug offenders. Interestingly, the percentages of female offenders was fairly high, at 16.4 per cent [ 36] . The Republic of Korea had a fairly sizeable population of methamphetamine abusers. A survey conducted in 1987 revealed that 1.4 per cent of working adolescents reported methamphetamine use. The prevalence rose to 9.6 per cent among institutionalized disturbed adolescents. A study of 817 amphetamine users in prison in December 1988 and January 1989 showed a high prevalence of intravenous injecting, at 90 per cent. About 63 per cent of intravenous methamphetamine users in a mental hospital between 1986 and 1990 were female ( [ 37] ,. pp. 2-3).

In the past, China. was very successful in controlling opium use. However, the last few years have seen the re-emergence of opium and heroin abuse and trafficking, particularly in Yunnan province, adjacent to the Golden Triangle area of Myanmar. About 30 per cent of heroin abusers along the border area of Yunnan administered the drug by intravenous injecting [ 38] .

The heroin epidemic in Japan during the 1950s was effectively dealt with. The number of violators of the heroin narcotics law ranged from only 30 to 98 persons between 1984 and 1989. The number of violators of the law on stimulants was far greater, from 16,848 to 24,346, during the same period of time ( [ 3] , p. 25). The violators of the drug control laws were drug abusers. Official statistics of the law enforcement authorities did not indicate the method of drug administration. However, injecting was known to be common among violators of the narcotics law and, to a lesser extent, the law on stimulants [ 39] . Hence, there are probably thousands of drug injectors currently in Japan.

Table 2 shows the prevalence of drug injecting in countries and areas of South-East Asia and East Asia.

Table 2. Estimated prevalence of drug injecting among the population of drug abusers In countries and areas of South -East Asia and East Asia

Country or area

Substance abused

Drug Injecting prevelance(percentage or frequency of abuse)

Hong Kong
Heroin
Up to 65
Indonesia
Heroin
..
Japan
Heroin
..
 
Amphetamine
..
Malaysia
Heroin
Up to 50
Myanmar
Heroin
Up to 90
Philippines
Heroin
<10
Republic of Korea
Methamphetamine
High
Singapore
Heroin
Very rare
Taiwan Province
Heroin
High
 
Morphine
High
Thailand
Opium
Up to 40
 
Heroin
Up to 95
Viet Nam
Opium
Up to 95

HIV infection among injecting drug users

The date of first discovery of AIDS and HIV infection, as opposed to the date of actual introduction of HIV, probably varied considerably from country to country, depending on such factors as the degree of monitoring and the methodology used in the country concerned. Most Asian countries reported their first cases in the mid-1980s. Injecting drug users so far appear not to have been involved in the first cases. In Singapore, the first case of HIV infection in a young homosexual man was reported in May 1985 [ 40] , while the HIV infection in intravenous drug users was first detected in the latter half of 1990 [ 35] . At the Municipal Narcotics Abstention Institute in Taiwan Province, 390 institutionalized opiate abusers by parenteral injecting were subjected to serum screening between December 1985 and February 1988. All the results were negative [ 36] . The small numbers of arrested cases of intravenous methamphetamine users in the Republic of Korea, 3, 187 and 245 cases in 1988, 1989 and 1990, respectively, were subjected to serum screening. AU results were negative ( [ 37] , p. 6). Although Japan had a substantial number of amphetamine users, drug injecting was apparently not common. Up to 1990, among the total of 290 AIDS cases and 1,412 HIV seropositives, only one case of an intravenous drug user was found. However, 207 of the AIDS cases and 1,209 of the cases of HIV infection were haemophiliacs. The first case of AIDS was found in March 1985 [ 41] .

Indigenous use of opium was somewhat similar in Nepal and Sri Lanka. Drug injecting was not the primary route of administration. The prevalence of HIV infection among drug abusers was probably still low. The first case of AIDS in Nepal, that of a 29 - year - old European male on temporary stay, was diagnosed in July 1988. Up to June 1990, 446 drug dependents had undergone serum screening. Only one case was found seropositive, that of a foreigner who was a drug abuser [ 42] . Sri Lanka had until late 1990 only 27 identified cases of HIV infection and AIDS, six of which were foreigners. Local cases involved 4 females and 17 males ( [ 14] , p. 2).

As indicated earlier, the population of intravenous drug abusers ill Hong Kong was quite large. The territory had a continuous influx of large numbers of foreign visitors for pleasure and trade. The administration had established a serum-screening service for the drug-dependent population under treatment in 1985. Up to September 1990, 4,518 cases had been tested, with only I seropositive case in 1990. A survey of a limited number of the drug dependents showed that most had shared needles. The first case of AIDS was identified in February 1985. The cumulative case number up to September 1990 was 190 HIV seropositives and 42 AIDS cases [ 43] . Despite the large number of intravenous drug abusers who shared needles, the transmission of HIV infection in this high-risk population nevertheless seemed very low.

The extremely rapid spread of HIV infection among the population of injecting drug abusers was also noted in Asia. In the State of Manipur in India, adjacent to Myanmar, serum screening for HIV antibodies has been carried out since July 1986. Up to September 1989, 2,322 samples had been tested, and no positive case found. In October 1989, HIV antibodies were detected in a 39-year-old businessman who injected drugs intravenously and was involved in smuggling and sexual promiscuity. From October 1989 to June 1990, 1,564 serum samples were collected from intravenous drug abusers. There were 853 HIV- seropositive cases, or 54.5 per cent [ 44] .

The first AIDS case in Thailand was identified in 1984 [ 45] . Continuous monitoring of HIV infection among the drug dependents entering treatment services was launched at the end of August 1987 at the Thanyarak Hospital, a large 250-bed hospital for the treatment of drug dependence, handling between 8,000 and 10,000 cases annually. Clients came from Bangkok and most provinces of the country. The monthly HIV-seropositive prevalence was about 1 per cent up to the end of 1987. During the first eight months of 1988, prevalence rose sharply to a maximum level of 33 per cent, and declined slightly throughout the following months [ 46] . A similar rapid rise in seropositive prevalence among the population of drug dependents under treatment was also simultaneously observed in the biennial cross-sectional sampling and seroscreening in the network of outpatient methadone detoxification clinics of the Bangkok Metropolitan Health Department. HIV-seropositive prevalence reached a level of about 40 per cent in September 1988 [ 47] . Continuous monitoring at Hatyai Hospital, in Song Khla province in the southern region bordering Malaysia, showed the same rapid rise of HIV seropositives, starting eight months after Bangkok, in October 1988 [ 48] .

According to official internal documents, surveillance of HIV infection and HIV seroscreening in Myanmar began in 1985, but have been conducted annually only since 1987. From 1985 to 1988, Yangon was the only sample city. The number of sample cities increased to 6,8 and 27 in 1989, 1990 and 1991, respectively. The first case of a drug dependent who was HIV-seropositive occurred in 1989. The seropositive percentages in the aggregate statistics increased rapidly, from 17.3 per cent, or 54 out of a total of 313 cases between 1985 and 1989, to 62.8 per cent, or 440 out of a total of 701 cases in 1990, to 77.2 per cent, or 474 out of a total of 614 cases between January and June 1991 [ 49] . In fact, the monthly prevalence of HIV seropositives among intravenous heroin users treated at the Drug Dependence Treatment and Research Unit of Yangon Psychiatric Hospital was even higher, with 43 seropositives out of 59 cases (72.9 per cent) in May 1989, and between 81.3 to 91.3 per cent during the months between May and September 1990 [ 50] .

From South -West Asia to East Asia, extreme differences in patterns of HIV infection and transmission in the population of drug abusers have been noted, with both very low and very high levels, and with both a slow and a rapid rise, of seropositive prevalence.

Concluding remarks

The patterns of drug abuse in Asian countries show considerable variation, with opium and heroin being the dominant drugs of abuse. Countries around the opiate-producing areas appear to have suffered a greater degree of abuse. Apart from opiates, amphetamine has been the primary drug of abuse in a few countries in East Asia, such as Japan and the Republic of Korea. However, the extent of abuse has been less than opiate abuse in other countries. Four patterns of drug abuse and injecting could be observed. First, there is the pattern in countries of South-West Asia and South Asia, where abuse has tended to involve smoking and inhaling heroin. Drug injecting has not been the primary mode of administration in most of the region, except in areas neighbouring on the Golden Triangle of South-East Asia. Secondly, opium and heroin abuse has dominated in the south-eastern region. Countries around the Golden Triangle seem to have suffered severe opiate abuse with a high prevalence of intravenous injecting. Thirdly, there is the pattern found among island nations such as Indonesia, the Philippines and Singapore, which have suffered comparatively little opiate abuse and a very low drug-injecting rate. The drug abuse situation in Hong Kong has been similar to that of countries in the Golden Triangle. Japan and the Republic of Korea exemplified the fourth pattern, which seemed distinct from that of the rest of Asia. In those countries, amphetamine abuse has been considerable, with injecting common in the Republic of Korea, but much less so in Japan.

The overall picture of drug injecting appears to replicate the diversity of drug abuse. Abusers who used similar substances in different places could prefer different methods of administration. Different areas of a country could have quite different rates of injecting the same substance. Perhaps the most remarkable new pattern is the extremely high prevalence of intravenous opium injecting in Viet Nam. It is also noteworthy that the recent appearance of increased intravenous heroin injecting in the State of Manipur in India and in Yunnan province in China has finally closed the gap in the circle of high prevalence of opiate abuse and high intravenous injecting around the Golden Triangle. Drug injecting appears to have progressively expanded during the past decade into areas of high population density with a harsh socioeconomic environment.

The great variation in the prevalence and transmission of HIV infection among the population of drug abusers confirms the reality of certain barriers and the influence of factors that seem to operate in different ways in different parts of Asia. In terms of inducing injection and HIV transmission, factors related to the substance used, although important, seem of less influence than those related to demographics and sociobehavioural characteristics. The areas of recent escalation of injecting drug abuse appear to have suffered concurrently from a rapid transmission of HIV infection. The recent changes send a strong message that the population of drug abusers is indeed the group most vulnerable to the rapid transmission of HIV infection.

If drug injecting proves to be the main route of transmission of HIV infection, as the patterns indicate, then the prevention of drug injecting is of paramount importance to Asian countries in their efforts to control the spread of HIV infection. Consideration could be given to preventing transmission through a more fundamental approach than, for example, discouraging injecting drug users from sharing needles and encouraging safer needle use. Efforts could be directed towards dissuading the population of drug abusers from injecting at all, or towards stopping the occurrence or expansion of drug abuse. The benefits to the world community would be twofold, as it would become possible for society to overcome the destructive impact of the twin scourges of drug abuse and HIV infection. Admittedly, such an effort would be more complex and difficult to plan, coordinate and implement. However, the concurrent development of and interrelationship between drug abuse and HIV infection clearly requires a determined effort to eradicate the two phenomena simultaneously.

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