Around 30% of the intravenous drug users (IVDUs) in Chennai, India, are infected with HIV, and around one out of six of these has passed the infection onto their regular sex partners, according to a cross-sectional study published in the May 1st edition of the Journal of Acquired Immune Deficiency Syndrome. Once HIV prevalence among a high-risk IVDU population becomes so high, the paper says “HIV epidemics can become self-perpetuating, with even modest levels of risk behaviour leading to substantial rates of infection. And yet very few of the participants in this study, including those who were infected, thought that they were at any risk of contracting HIV.”
Furthermore, sharing needles was not the only risky behaviour this study population engaged in. Many of the participants had risky sex with multiple partners (including sex workers), although this was not significantly associated with a greater risk of being infected in this population. However, there was one factor unrelated to injection-related risks that was significantly associated with participants being infected: getting a street-corner tattoo.
HIV and injection drug use in India
No one really knows exactly how many people in India are HIV-infected. UNAIDS estimates in 2004 put the number up to around 5.1 million, but the number could in fact be much higher. It is believed that the epidemic is primary spread by unprotected heterosexual intercourse, but Indian epidemiology research tends to focus on individual risk factors and does not analyse the lifestyles of Indians at risk too deeply.
A good example of this is injection drug use. IV drug use is a common means of HIV transmission in parts of Asia, including parts of India bordering Myanmar (although lately there has been a diffusion of IV drug use to other parts of India). HIV outbreaks among IVDUs in the northeastern states of India led the country to adopt targeted prevention interventions focused on safer injection practices. However, a number of studies in other Asian countries have reported that IVDUs also engage in a variety of risk behaviours that put themselves, and others, at risk of infection. For example, despite a popular misconception that injection drug use decreases libido, several studies find IVDUs are far more likely to have unprotected sex with multiple partners.
A study in Chennai
To learn more about the lives and risk behaviours of IVDUs in India, researchers decided to conduct a cross-sectional study (a one-time assessment) of risk-taking and HIV prevalence among IVDUs and their regular sex partners in Chennai, India. In the past ten years, injection drug use has become increasingly common in Chennai (India's third largest city, which is on the southeast coast of the country), but there have been no studies in this population.
The study employed peer outreach workers and field researchers to recruit 260 IVDUs and their wives or live-in sex partners living in central Chennai over a period of three months in 2003. After obtaining the participants’ informed consent, researchers used a questionnaire to gather information on the subjects’ socio-demographic profile, initiation of drug use, switching to injection drug, injection equipment sharing practices, sexual practices in and outside marriage, risk perception, and knowledge of HIV/AIDS. Each study participant also donated blood for anonymous HIV testing.
Complete data were available for 226 IVDUs and their regular sex partners. The HIV seroprevalence was 30% (68/226) in IDUs and 16% of these passed HIV onto their wives or live-in partners (11/226). This rate of onward transmission is low compared to some studies, and may reflect a rapid turnover of regular partners. Women who had been with their IVDU partners for more than six years were significantly more likely to be HIV-positive (p = 0.02).
Fifty-seven percent of the HIV-positive IVDUs and 45% of the HIV-infected women thought that they had “no chance” or “very little chance” of becoming infected.
Since such a low number of female partners in the study were infected, the researchers focused on the risk-taking behaviours among IVDUs.
Nearly 60% of the IVDUs (137/226) reported ever having sex with female commercial sex workers, however this was not associated with an increased risk of being HIV-positive. Neither was condom use. However, the IVDUs could have put the sex workers or other irregular sex partners at risk of infection, although the study did not address this.
Most of the risk factors that were most likely to be associated with HIV-infection were related to injection drug use, not surprising since more than 20% IVDUs reported borrowing or lending of injection equipment. In a univariate analyses, more than twice-a-day injecting frequency, and ever-injecting drugs in drug-selling places had a significant association with HIV-infection, together with a history of incarceration and recruitment from the northern part of the city. However, researchers tied both of these factors to injection drug use. Living in the northern part of the city was associated with worse economic status. Consequently, IVDUs living there are more likely to be forced to reuse needles. The researchers made the same association (a higher rate of needle-sharing) for those with a history of incarceration; unprotected sex in prison with other men did not appear to be addressed in the questionnaire.
Tattoos
Another interesting factor was associated with being HIV-infected in the univariate analysis: having a tattoo. This prompted a subsequent investigation into tattooing in Chennai. The researchers wrote: “Persons applying tattoos carry out their business from roadside pavements or by roaming the streets in Chennai. They also display their wares in festivals and weekly bazaars. Instead of battery-operated machines used by male tattoo makers, women belonging to nomadic tribes, who are also in such businesses, manually prick the skin repeatedly with solid sharp needles dipped in green dye or ink along the lines of the design drawn on the chosen part of the body. The time taken to complete a tattoo varies from 15 minutes to one hour, depending on the size of the design. Some wipe off the oozing blood with a strip of cloth, which has seen many usages. Some even advise not to wipe off the blood and let the wound heal by itself.”
The investigators continue “Talking with an injector revealed more details about tattooing in the city. He recalled being the fifth person in the line. Everyone took their turn and once the above-mentioned process was completed, the person applying the tattoo did not change the needle or clean it at all. The needle was in fact not even kept immersed in any kind of solution. This appeared to be the common practice in this business followed by most of the tattoo makers.”
In an adjusted analysis, having a tattoo still tended toward being significantly associated with HIV-infection (p=0.07) which suggests that HIV is probably being transmitted via this root. If so, then IVDUs are not likely to be the only group being infected this way.
Conclusion
However, in the adjusted model, the odds of HIV-infection were twice higher among IDUs who had ever injected drugs in drug-selling places and six times higher in those who were recruited from the northern part of central Chennai. This suggests that sharing needles is still the most significant risk factor for transmission. Nonetheless, the researchers conclude that “reducing the sharing of injection equipment and unsafe tattooing through targeted and environmental interventions, increasing HIV risk perception, and promoting safer sex practices among IDUs and their sex partners are urgent program needs.”
Panda S et al. Risk factors for HIV infection in injection drug users and evidence for Onward transmission of HIV to their sexual partners in Chennai, India. J Acquir Immune Defic Syndr 39: 9 - 15, 2005.