Mark W. Tyndall

Surviving the sex trade: a comparison of HIV risk behaviours among street-involved women in two Canadian cities who inject drugs.

In Canada, very little is known about the factors and processes that cause drug-related harm among female intravenous drug users (IDUs). Women who inject drugs and participate in the survival sex trade are considered to be at increased risk for sexual and drug-related harms, including HIV infection. Between September 1999 and September 2000, women participating in the VIDUS cohort in Vancouver and the St. Luc Cohort in Montreal completed interviewer-administered questionnaires. Analyses were conducted to compare the demographic characteristics, sexual risk behaviours, risky injection practices and drug use patterns among women who self-identified as participating in the sex trade with those who did not identify as participating in the sex trade. Logistic regression was used to identify factors independently associated with exchanging sex for money or drugs. HIV prevalence at the study visit (September 1999-2000) was 29% for sex trade workers and 29.2% for non-sex trade workers. While patterns of sexual risk were similar, the risky injection practice and drug use patterns between sex trade workers and non-sex trade workers were markedly different. Logistic regression analysis of cross-sectional data revealed that independent behaviours associated with the sex trade included: greater than once per day use of heroin (adjusted OR 2.7), smokeable crack cocaine (adjusted OR=3.3) and borrowing used syringes (adjusted OR=2.0). Creative, client-driven interventions are urgently needed for women who trade sex for money or for drugs.

Occupational stigma as a primary barrier to health care for street-based sex workers in Canada

Individuals working in the sex industry continue to experience many negative health outcomes. As such, disentangling the factors shaping poor health access remains a critical public health priority. Within a quasi-criminalised prostitution environment, this study aimed to evaluate the prevalence of occupational stigma associated with sex work and its relationship to barriers to accessing health services. Analyses draw on baseline questionnaire data from a community-based cohort of women in street-based sex work in Vancouver, Canada (2006–2008). Of a total of 252 women, 141 (55.9%) reported occupational sex work stigma (defined as hiding occupational sex work status from family, friends and/or home community), while 125 (49.6%) reported barriers to accessing health services in the previous six months. In multivariable analysis, adjusting for sociodemographic, interpersonal and work environment risks, occupational sex work stigma remained independently associated with an elevated likelihood of experiencing barriers to health access. Study findings indicate the critical need for policy and societal shifts in views of sex work as a legitimate occupation, combined with improved access to innovative, accessible and non-judgmental health care delivery models for street-based sex workers that include the direct involvement of sex workers in development and implementation.

Meth/amphetamine use and associated HIV: Implications for global policy and public health

Amphetamine type stimulants (ATS) have become the focus of increasing attention worldwide. There are understandable concerns over potential harms including the transmission of HIV. However, there have been no previous global reviews of the extent to which these drugs are injected or levels of HIV among users. A comprehensive search of the international peer-reviewed and grey literature was undertaken. Multiple electronic databases were searched and documents and datasets were provided by UN agencies and key experts from around the world in response to requests for information on the epidemiology of use. Amphetamine or methamphetamine (meth/amphetamine, M/A) use was documented in 110 countries, and injection in 60 of those. Use may be more prevalent in East and South East Asia, North America, South Africa, New Zealand, Australia and a number of European countries. In countries where the crystalline form is available, evidence suggests users are more likely to smoke or inject the drug; in such countries, higher levels of dependence may be occurring. Equivocal evidence exists as to whether people who inject M/A are at differing risk of HIV infection than other drug injectors; few countries document HIV prevalence/incidence among M/A injectors. High risk sexual behaviour among M/A users may contribute to increased risk of HIV infection, but available evidence is not sufficient to determine if the association is causal. A range of possible responses to M/A use and harm are discussed, ranging from supply and precursor control, to demand and harm reduction. Evidence suggests that complex issues surround M/A, requiring novel and sophisticated approaches, which have not yet been met with sufficient investment of time or resources to address them. Significant levels of M/A in many countries require a response to reduce harms that in many cases remain poorly understood. More active models of engagement with M/A users and provision of services that meet their specific needs are required.

Prevalence and Correlates of Untreated Human Immunodeficiency Virus Type 1 Infection among Persons Who Have Died in the Era of Modern Antiretroviral Therapy

We evaluated all human immunodeficiency virus (HIV)-related deaths over the period 1 January 1995-31 December 2001 in a Canadian province in which all HIV care and antiretroviral therapy are provided free of charge. Persons who had received antiretroviral drugs before death were compared with those who had died without ever receiving HIV treatment, by fitting a logistic model. Overall, 1239 deaths were attributed to HIV infection during the study period. Of these, 406 (32.8%) occurred among persons who had never received any HIV treatment. In adjusted analyses, aboriginal ethnicity, female sex, and lower median income were negatively associated with receiving HIV treatment before death. Furthermore, among the 833 individuals who received treatment before death, only 379 (45.5%) received antiretroviral medication >or=75% of the time during their first year receiving therapy. The data demonstrate the need for novel interventions to expand HIV care to specific populations.

Risky sexual behaviours among injection drugs users with high HIV prevalence: implications for STD control

Injection drug use is inextricably linked to commercial sex work and the transmission of sexually transmitted disease (STD). In many communities prevention efforts have been stalled owing to the marginal existence of this community. This study describes the sexual activities, condom use, reported STDs, and commercial sex work in a large cohort of injection drug users. Seventy two per cent of male and 92% of female subjects in the cohort were sexually active. Among female subjects, 57% reported more than 100 lifetime partners. Condoms were generally not used with regular partners, used about half the time with casual partners, and used about 80% of the time with paying partners. Female sex workers were more likely to have unstable housing and to report incarceration in the previous six months. Reducing the transmission of STDs and HIV in drug using communities is a public health priority. While existing prevention programmes should be strengthened, innovative approaches to STD surveillance, diagnosis, and prevention are needed.

Continued low uptake of treatment for hepatitis C virus infection in a large community-based cohort of inner city residents

Despite advances in HCV treatment, recent data on treatment uptake is sparse. HCV treatment uptake and associated factors were evaluated in a community‐based cohort in Vancouver, Canada.

An external evaluation of a peer-run "unsanctioned" syringe exchange program.

In Vancouver, British Columbia, Canada, difficulty accessing syringes at night has been shown to be strongly associated with human immunodeficiency virus (HIV) risk behavior among the city’s injection drug users (IDUs). On September 1, 2001, the Vancouver Area Network of Drug Users (VANDU) initiated an unsanctioned all-night needle-exchange program on a street corner in the heart of the neigh-borbood where many of the city’s IDUs are concentrated. An external evaluation of the population reached by the VANDU exchange was performed through the Vancouver Injection Drug User’s Study, a prospective cohort study of IDUs begun in 1996. Persons accessing syringes through the exchange were compared to those active injectors who acquired their syringes from other sources, including the city’s fixed site exchange, which closes at 8:00 pm. Overall, 587 active IDUs were seen during the period September 2001 to june 2002; of these individuals. 165 (28.1%) reported using the VANDU exchange. In multivariate analyses, participants who used the VANDU table were more likely to frequently inject cocaine (adjusted odds ratio [AOR]=1.56; 95% confidence interval [CI]=1.00–2.44), inject in public (AOR=2.71; 95% CI=1.62–4.53), and require help injecting (OR=2.13; 95% CI=1.33–3.42). Interestingly, use of the table was also independently associated with safer syringe disposal (AOR=2.69; 95% CI-1.38–5.21). Results indicate that the unsanctioned exchange appears to have reached those IDUs at highest risk of HIV infection. Although the cross-sectional nature of the study design warrants caution, we also found that use of the nighttime exchange was strongly associated with higher rates of safe syringe disposal. The data suggest that drug user organizations can play a major role in reducing harm among their peers by reaching the highest risk drug users with harm reduction services. The findings also suggest that other forms of syringe-exchange programs should consider the benefits of offering fixed site nighttime service.

Access and utilization of HIV treatment and services among women sex workers in Vancouver’s downtown eastside

Many HIV-infected women are not realizing the benefits of highly active antiretroviral therapy (HAART) despite significant advancements in treatment. Women in Vancouver’s Downtown Eastside (DTES) are highly marginalized and struggle with multiple morbidities, unstable housing, addiction, survival sex, and elevated risk of sexual and drug-related harms, including HIV infection. Although recent studies have identified the heightened risk of HIV infection among women engaged in sex work and injection drug use, the uptake of HIV care among this population has received little attention. The objectives of this study are to evaluate the needs of women engaged in survival sex work and to assess utilization and acceptance of HAART. During November 2003, a baseline needs assessment was conducted among 159 women through a low-threshold drop-in centre servicing street-level sex workers in Vancouver. Cross-sectional data were used to describe the sociodemographic characteristics, drug use patterns, HIV/hepatitis C virus (HCV) testing and status, and attitudes towards HAART. High rates of cocaine injection, heroin injection, and smokeable crack cocaine use reflect the vulnerable and chaotic nature of this population. Although preliminary findings suggest an overall high uptake of health and social services, there was limited attention to HIV care with only 9% of the women on HAART. Self-reported barriers to accessing treatment were largely attributed to misinformation and misconceptions about treatment. Given the acceptability of accessing HAART through community interventions and women specific services, this study highlights the potential to reach this highly marginalized group and provides valuable baseline information on a population that has remained largely outside consistent HIV care.

A dose-response relationship between exposure to a large-scale HIV preventive intervention and consistent condom use with different sexual partners of female sex workers in southern India

BackgroundThe Avahan Initiative, a large-scale HIV preventive intervention targeted to high-risk populations including female sex workers (FSWs), was initiated in 2003 in six high-prevalence states in India, including Karnataka. This study assessed if intervention exposure was associated with condom use with FSWs’ sexual partners, including a dose-response relationship.MethodsData were from a cross-sectional study (2006-07) of 775 FSWs in three districts in Karnataka. Survey methods accounted for the complex cluster sampling design. Bivariate and multivariable logistic regression was used to separately model the relationships between each of five intervention exposure variables and five outcomes for consistent condom use (CCU= always versus frequently/sometimes/never) with different sex partners, including with: all clients; occasional clients; most recent repeat client; most recent non-paying partner; and the husband or cohabiting partner. Linear tests for trends were conducted for three continuous intervention exposure variables.ResultsFSWs reported highest CCU with all clients (81.7%); CCU was lowest with FSWs’ husband or cohabiting partner (9.6%). In multivariable analysis, the odds of CCU with all clients and with occasional clients were 6.3-fold [95% confidence intervals, CIs: 2.8-14.5] and 2.3-fold [95% CIs: 1.4-4.1] higher among FSWs contacted by intervention staff and 4.9-fold [95% CIs: 2.6-9.3] and 2.3-fold [95% CIs: 1.3-4.1] higher among those who ever observed a condom demonstration by staff, respectively, compared to those who had not. A significant dose-response relationship existed between each of these CCU outcomes and increased duration since first contacted by staff (P=0.001; P=0.006) and numbers of condom demonstrations witnessed (P=0.004; P=0.026); a dose-response relationship was also observed between condom use with all clients and number of times contacted by staff (P=0.047). Intervention exposure was not associated with higher odds of CCU with the most recent repeat client, most recent non-paying partner or with the husband or cohabiting partner.ConclusionStudy findings suggest that exposure to a large-scale HIV intervention for FSWs was associated with increased CCU with commercial clients. Moreover, there were dose-response relationships between CCU with clients and increased duration since first contacted by staff, times contacted by staff and number of condom demonstrations. Additional program effort is required to increase condom use with non-commercial partners.

Unstable housing and hepatitis C incidence among injection drug users in a Canadian setting

BackgroundThere has emerged growing recognition of the link between housing and health. Since Vancouver, Canada has had increasing concerns with homelessness brought about by urban renewal in the lead-up to the 2010 Winter Olympic Games, we evaluated hepatitis C virus (HCV) incidence among injection drug users (IDU) with and without stable housing.MethodsData were derived from a collaboration between two prospective cohort studies of IDU in Vancouver, Canada. Using Cox Proportional Hazards regression, we compared HCV incidence among participants with and without stable housing, and determined independent predictors of HCV incidence.ResultsOverall, 3074 individuals were recruited between May 1996 and July 2007, among whom 2541 (82.7%) were baseline HCV-infected. Among the 533 (17.3%) individuals who were not HCV-infected at baseline, 147 tested HCV antibody-positive during follow-up, for an incidence density of 16.89 (95% confidence interval: 14.76 – 19.32) per 100 person-years. In a multivariate Cox regression model, unstable housing remained independently associated with HCV infection (relative hazard = 1.47 (1.02 – 2.13).ConclusionHCV prevalence and incidence are high in this setting and were associated with unstable housing. Efforts to protect existing low-income housing and improve access to housing may help to reduce HCV incidence.