Risk factors of HIV infection and needle sharing among injecting drug users in Ho Chi Minh City, Viet Nam

Abstract

Objective: We sought to identify risk factors for needle sharing and HIV infection among injecting drug users (IDUs) in Ho Chi Minh City (HCMC), Viet Nam. Methods: Three cross-sectional surveys among IDUs, both on the street (in 11 urban districts) and in the rehabilitation center for IDUs in HCMC, were carried out in April of 1995, 1997, and 1998. Outreach workers interviewed IDUs about socio-demographic characteristics, drug use and sexual practices, and HIV knowledge and perceptions. The IDUs were also tested for seropositivity to HIV. Independent predictors for HIV positivity and needle sharing were determined by univariate and multivariate logistic regression for the study sample within the rehabilitation center in 1997 and for that on the street in 1998. Results: The HIV prevalence in 1998 among IDUs was 44% for those on the street and 38.5% for those in the rehabilitation center. Independent predictors for HIV infection in IDUs were being injected by drug dealers (for the 1997 sample), injecting on the street, and sharing the drug pots (for the 1998 sample). The reported rate of needle sharing was low and decreased significantly from 20% in 1995 to 12% in 1998 for the sample of IDUs at the street. In the multivariate analysis, predictors for needle sharing for both study samples were injecting on the street, injecting at shooting galleries, and having shared needles in the past. Adequate and easy access to sterile needles and syringes, and an supportive environment of behavior change, especially in street and shooting gallery could reduce risks of virus transmission in the Vietnamese IDU community.

Introduction

At a global level, the mode of HIV-1 transmission through sexual contact is predominant (WHO/UNAIDS, 1998). However, shared use of injection equipment, identified as the primary causal link between drug injection and HIV infection (Schoenbaum et al., 1989), has played a critical role in fueling a number of local, national, and regional HIV epidemics. By 1996, HIV infection among injecting drug users (IDUs) had been reported in 83 countries. The HIV prevalence in the drug injecting population was high in southern Europe, the northeastern region of the United States, and parts of Asia and South America (Stimson & Choopanya, 1998). Viet Nam belongs to a number of countries in Asia and the Pacific region, which have separate but explosive epidemics among their IDU populations, such as Thailand, Myanmar, India (Manipur), Malaysia, Nepal, and China (Dore, Brown, Tarantola, & Kaldor, 1998).

From all provinces in Viet Nam, 29,116 HIV positive persons had been reported as of 18 January 2001 (Weekly HIV/AIDS Report of the Viet Nam National Institute of Hygiene and Epidemiology, 20 January 2001). A majority of the total reported HIV (64%) and AIDS (77%) cases in the country were IDUs. The results of HIV sentinel surveillance also show that HIV infection in Viet Nam is primarily associated with injecting drug use, but its extent is highly variable throughout the country. In 1998, HIV prevalence among IDUs was more than 10% in 11 of 20 sentinel provinces, with an aggregated prevalence rate of 13%. Other prevalence rates were 2.4% among female sex workers (FSWs); 0.7% among sexually transmitted disease (STD) patients and less than 0.15% among antenatal women and army conscripts (Hien et al., 1999). However, since 1997, there have been explosive increases in HIV prevalence among IDUs in many northern provinces, such as Lang son, Quang ninh, and Hai phong. It is clear that in Viet Nam, HIV infection is rapidly and predominantly being transmitted among IDUs through sharing needles and syringes with an aggregated rate of 20.4% in 1999. In 2000, the HIV prevalence was very high in many provinces such as Binh Dinh (44.7%), Quang ninh (49.6%), Hai phong (70.4%), Da Nang (37.5%), Vung tau (54.7%), and Ho Chi Minh City (HCMC; 58.1%) (Ministry of Health, Viet Nam, 2001). By the year 2000, the cumulative number of HIV infections in Viet Nam is estimated to reach 135,000–160,000 cases. Among them, approximately 21,000 will be IDUs (WHO/WPRO, 1998).

HCMC reported the highest number of HIV infection. It accounts for 16.8% of total reported cases in the country. By risk category, the vast majority of HIV infections in HCMC were among IDUs. The HIV epidemic in Viet Nam first started in HCMC. The HIV prevalence rate among IDUs rose rapidly from 3% in 1992 to 33% in 1994 and 44% in 1996. In response to the increased epidemic, many prevention efforts in the city since 1995 continue to be active among IDUs. These include the IEC AIDS prevention campaign, outreach and education programs, peer education, a telephone hotline, home care and counseling, and pilot needle and syringes provision (Lindan et al., 1997).

In Thailand, HIV transmission among IDUs and from IDUs to the rest of the population was experienced in four epidemic waves over just a few years: the first wave among IDUs, the second among FSWs, the third among male STD patients, and the fourth among nonprostitute women, infants, and others (Weniger et al., 1991). The challenge facing Viet Nam is to prevent a similar development of the epidemic.

Despite the rapid spread of HIV infection among IDUs in Viet Nam, little is known about their drug injecting and sexual behaviors, which are arguably the major risk factors for HIV transmission. The main objective of this study was to identify risk factors for both needle sharing and HIV infection among those IDUs in HCMC, where the HIV epidemic among IDUs started earlier and spread rapidly, with significant implications for HIV prevention among IDUs in Viet Nam.