At the borders, on the edge: use of injected methamphetamine in Tijuana and Ciudad Juarez, Mexico

Social and structural determinants of injection drug use-associated bacterial and fungal infections: A qualitative systematic review and thematic synthesis

BACKGROUND AND AIMS

Injection drug use-associated bacterial and fungal infections are increasingly common, and social contexts shape individuals' injecting practices and treatment experiences. We sought to synthesize qualitative studies of social-structural factors influencing incidence and treatment of injecting-related infections.

METHODS

We searched PubMed, EMBASE, Scopus, CINAHL and PsycINFO from 1 January 2000 to 18 February 2021. Informed by Rhodes' 'risk environment' framework, we performed thematic synthesis in three stages: (1) line-by-line coding; (2) organizing codes into descriptive themes, reflecting interpretations of study authors; and (3) consolidating descriptive themes into conceptual categories to identify higher-order analytical themes.

RESULTS

We screened 4841 abstracts and included 26 qualitative studies on experiences of injecting-related bacterial and fungal infections. We identified six descriptive themes organized into two analytical themes. The first analytical theme, social production of risk, considered macro-environmental influences. Four descriptive themes highlighted pathways through which this occurs: (1) unregulated drug supply, leading to poor drug quality and solubility; (2) unsafe spaces, influenced by policing practices and insecure housing; (3) health-care policies and practices, leading to negative experiences that discourage access to care; and (4) restrictions on harm reduction programmes, including structural barriers to effective service provision. The second analytical theme, practices of care among people who use drugs, addressed protective strategies that people employ within infection risk environments. Associated descriptive themes were: (5) mutual care, including assisted-injecting and sharing sterile equipment; and (6) self-care, including vein health and self-treatment. Within constraining risk environments, some protective strategies for bacterial infections precipitated other health risks (e.g. HIV transmission).

CONCLUSIONS

Injecting-related bacterial and fungal infections are shaped by modifiable social-structural factors, including poor quality unregulated drugs, criminalization and policing enforcement, insufficient housing, limited harm reduction services and harmful health-care practices. People who inject drugs navigate these barriers while attempting to protect themselves and their community.

Driving under the influence: a multi-center evaluation of vehicular crashes in the era of cannabis legalization

Background

Eleven states have instituted laws allowing recreational cannabis use leading to growing public health concerns surrounding the effects of cannabis intoxication on driving safety. We hypothesized that after the 2016 legalization of cannabis in California, the use among vehicular injury patients would increase and be associated with increased injury severity.

Methods

San Diego County’s five adult trauma center registries in were queried from January 2010 to June 2018 for motor vehicle or motorcycle crash patients with completed toxicology screens. Patients were stratified as toxicology negative (TOX−), positive for only THC (THC+), only blood alcohol >0.08% (ETOH+), THC+ETOH, or THC+ with any combination with methamphetamine or cocaine (M/C). County medical examiner data were reviewed to characterize THC use in those with deaths at the scene of injury.

Results

Of the 11,491 patients identified, there were 61.6% TOX−, 11.7% THC+, 13.7% ETOH+, 5.0% THC+ETOH, and 7.9% M/C. THC+ increased from 7.3% to 14.8% over the study period and peaked at 14.9% post-legalization in 2017. Compared with TOX− patients, THC+ patients were more likely to be male and younger. THC+ patients were also less likely to wear seatbelts (8.5% vs 14.3%, p<0.001) and had increased mean Injury Severity Score (8.4±9.4 vs 9.0±9.9, p<0.001) when compared with TOX− patients. There was no difference in in-hospital mortality between groups. From the medical examiner data of the 777 deaths on scene, 27% were THC+.

Discussion

THC+ toxicology screens in vehicular injury patients peaked after the 2016 legalization of cannabis. Public education on the risks of driving under the influence of cannabis should be a component of injury prevention initiatives.

Level of evidence

III, Prognostic

The Role of Gender in the Health and Human Rights Practices of Police: The SHIELD Study in Tijuana, Mexico

Globally, punitive drug law enforcement drives human rights violations. Drug control tactics, such as syringe confiscation and drug-related arrests, also cascade into health harms among people who use drugs. The role of police officer characteristics in shaping such enforcement and measures to reform police practices remains underexamined. We evaluated gender differences in syringe confiscation and syringe-related arrest behaviors among municipal police officers in Tijuana, Mexico, where syringe possession is legal. In the context of the SHIELD Study focusing on aligning policing with harm reduction measures, our baseline sample covered municipal police officers who reported having occupational contact with syringes. We used multivariable logistic regression with robust variance estimation via a generalized estimating equation to identify correlates of syringe-related policing behaviors. Among respondent officers (n=1,555), 12% were female. After considering possible confounding variables, such as district of service and work experience, female officers were significantly less likely to report confiscating syringes or arresting individuals for syringe possession. Consideration of officer gender is important in the design of interventions to improve the health and human rights of people who inject drugs and other highly policed groups, as well as measures to safeguard officer occupational safety. The feminization of law enforcement deserves special consideration as an imperative in reducing the public health harms of policing.

Structural factors associated with methamphetamine smoking among female sex workers in Tijuana, Mexico

INTRODUCTION AND AIMS

Smoking methamphetamine is associated with increased risk of HIV among female sex workers (FSW). The structural context of substance use is an important shaper of individual behaviour; however, structural determinants of methamphetamine use among FSWs are largely unknown. We identified individual, structural and neighbourhood factors associated with smoking methamphetamine among FSWs in the border city of Tijuana, Baja California, Mexico.

DESIGN AND METHODS

A prospective cohort of 301 FSWs sampled from indoor and outdoor sex work venues throughout Tijuana participated in quantitative surveys on behaviours and mapping of home and work neighbourhoods across three visits. Multinomial logistic regression using generalised estimating equations identified individual, structural and neighbourhood variables associated with smoking methamphetamine.

RESULTS

Methamphetamine use, particularly smoking, was highly prevalent among FSWs. Over half (61%) of FSWs had ever used methamphetamine in their lifetime and at baseline, 38% currently smoked methamphetamine. Smoking methamphetamine daily was associated with living in the red light district [adjusted odds ratio (AOR) = 2.72, 95% confidence interval (CI) = 1.23-6.02] and with perceived homelessness, but only among women in a good financial situation (AOR = 4.08, 95% CI = 1.58-10.50). Smoking methamphetamine less than daily was associated with older age (AOR = 1.06, 95% CI = 1.02-1.10).

DISCUSSION AND CONCLUSIONS

Our findings point to the important dynamic between the residential environment and more severe methamphetamine use. FSWs may prioritise the purchase of methamphetamine over stable housing if they have the financial means. Given the high prevalence of smoking methamphetamine among FSWs in Tijuana, drug treatment options, especially for women living in the red light district, are needed.

Predictors of injecting cessation among a cohort of people who inject drugs in Tijuana, Mexico

INTRODUCTION

Little is known about the cessation of injecting drug use (IDU) among people who inject drugs (PWID) in low and middle-income settings, where access to effective interventions for reducing drug use (e.g., opioid substitution treatment; OST), may be limited. We measured the incidence and identified predictors of IDU cessation among a cohort of PWID in Tijuana, Mexico.

METHODS

Data were drawn from 621 participants in Proyecto El Cuete IV, a prospective cohort of PWID recruited in 2011 and interviewed biannually to 2016. A multivariable Extended Cox model was constructed to identify socio-demographic, drug use, risk environment and health-related predictors of IDU cessation (no IDU for ≥six months).

RESULTS

141 participants (23%) reported at least one IDU cessation event during follow-up. The crude IDU cessation rate was 7.3 per 100 person-years (95% Confidence Interval [CI]: 6.2-8.7). IDU cessation was negatively associated with injecting at least daily on average and heroin/methamphetamine co-injection in the past six months, and positively associated with testing HIV positive at baseline, being on methadone maintenance therapy in the past six months, and recent arrest. Concern for personal safety was also independently associated with IDU cessation.

CONCLUSIONS

The rate of IDU cessation among PWID in Tijuana was low. These findings underscore the importance of expansion of services including OST to help reduce drug use and facilitate IDU cessation for those who wish to do so. In this setting, interventions addressing individual-level economic barriers as well as broader social and structural barriers to harm reduction services are integral.

Prevalence and Correlates of Heroin-Methamphetamine Co-Injection Among Persons Who Inject Drugs in San Diego, California, and Tijuana, Baja California, Mexico

OBJECTIVE

Although persons who inject drugs (PWID) in the western United States-Mexico border region are known to inject both heroin and methamphetamine, little is known about the prevalence and risks associated with co-injection of this depressant-stimulant combination (also known as "goofball" and "Mexican speedball").

METHOD

Baseline data from parallel cohort studies of PWID conducted concurrently in San Diego, CA, and Tijuana, Mexico, were used to estimate the prevalence and identify correlates of heroin-methamphetamine co-injection. PWID older than 18 years of age who reported injecting illicit drugs in the past month (N = 1,311; 32.7% female) were recruited in San Diego (n = 576) and Tijuana (n = 735) and completed interviewer-administered questionnaires. Bivariate and multivariable logistic regression analyses were used to identify correlates of heroin-meth-amphetamine co-injection.

RESULTS

The prevalence of co-injection in the past 6 months was 39.9% overall and was higher in Tijuana (55.8%) than in San Diego (19.8%). In multivariable analyses adjusting for study cohort, distributive syringe sharing, purchasing syringes prefilled with drugs, finding it hard to get new syringes, reporting great or urgent need for treatment, and younger age were independently associated with co-injection. Past-6-month overdose was significantly associated with higher odds of co-injection in San Diego than in Tijuana.

CONCLUSIONS

These findings indicate that heroin-methamphetamine co-injection is more common in Tijuana than in San Diego, yet this practice was only associated with overdose in San Diego. Heroin-methamphetamine coinjection was also independently associated with HIV-associated injection risk behaviors. Overdose-prevention interventions should address co-injection of depressants and stimulants.

Police Victimization Among Persons Who Inject Drugs Along the U.S.-Mexico Border

OBJECTIVE

Problematic policing practices are an important driver of HIV infection among persons who inject drugs (PWID) in the U.S.-Mexico border region. This study identifies factors associated with recent (i.e., past 6 months) police victimization (e.g., extortion, physical and sexual violence) in the border city of Tijuana, Mexico.

METHOD

From 2011 to 2013, 733 PWID (62% male) were recruited in Tijuana and completed a structured questionnaire. Eligible participants were age 18 years or older, injected illicit drugs within the past month, and spoke Spanish or English. Multivariable logistic regression analyses identified correlates of recent experiences of police victimization (e.g., bribes, unlawful confiscation, physical and sexual violence).

RESULTS

Overall, 56% of PWID reported a recent police victimization experience in Tijuana. In multivariable logistic regression analyses, factors independently associated with recent police victimization included recent injection of methamphetamine (adjusted odds ratio [AOR] = 1.62; 95% CI [1.18, 2.21]) and recently received injection assistance by a "hit doctor" (AOR = 1.56; 95% CI [1.03, 2.36]). Increased years lived in Tijuana (AOR = 0.98 per year; 95% CI [0.97, 0.99]) and initiating drug use at a later age (AOR = 0.96 per year; 95% CI [0.92, 0.99]) were inversely associated with recent police victimization.

CONCLUSIONS

Physical drugusing markers may increase PWID susceptibility to police targeting and contribute to experiences of victimization. Interventions aimed at reducing police victimization events in the U.S.-Mexico border region should consider PWID's drug-using behaviors. Reducing problematic policing practices may be a crucial public health strategy to reduce HIV risk among PWID in this region.

Incidence and Predictors of HIV and Sexually Transmitted Infections Among Female Sex Workers and Their Intimate Male Partners in Northern Mexico: A Longitudinal, Multilevel Study

Preventing human immunodeficiency virus (HIV) infection and other sexually transmitted infections (STIs) requires an understanding of sexual relationship factors beyond the individual level. We estimated HIV/STI incidence and identified time-varying predictors of STI acquisition in a prospective cohort study of female sex workers and their intimate (noncommercial) male partners in northern Mexico. From 2010 to 2013, couples underwent behavioral and biological assessments biannually for 24 months. Among 413 initially HIV-uninfected participants, 8 seroconverted during follow-up. Incidence of HIV (1.12 cases/100 person-years (PY)), chlamydia (9.47 cases/100 PY), active syphilis (4.01 cases/100 PY), and gonorrhea (1.78 cases/100 PY) was higher among women than among men (HIV: P = 0.069; all STIs combined: P < 0.001). In multivariable conditional logistic regression with individual fixed effects and correlated error terms within couples, risk of STI acquisition was significantly higher among women who had recently used cocaine, crack, or methamphetamine (adjusted odds ratio (OR) = 2.13, 95% confidence interval (CI): 1.07, 4.28). STI risk was lower among women who reported physically assaulting their male partners (adjusted OR = 0.44, 95% CI: 0.22, 0.86) and among men whose female partners had regular sex-work clients (adjusted OR = 0.38, 95% CI: 0.14, 1.03). Improving vulnerable couples' sexual health will require addressing the contexts in which drug use, interpersonal conflict, and economic vulnerability converge.

Prevalence and correlates of neck injection among people who inject drugs in Tijuana, Mexico

INTRODUCTION AND AIMS

Injecting drugs in the neck has been related to adverse health conditions such as jugular vein thrombosis, deep neck infections, aneurysm, haematomas, airway obstruction, vocal cord paralysis and wound botulism, among others. We identified prevalence and correlates of neck injection among people who inject drugs (PWID) in Tijuana, Mexico.

DESIGN AND METHODS

Beginning in 2011, PWID aged ≥18 years who injected drugs within the last month were recruited into a prospective cohort. At baseline and semi-annually, PWID completed interviewer-administered surveys soliciting data on drug-injecting practices. Logistic regression was used to identify predictors of injecting in the neck as the most frequent injection site at a single visit.

RESULTS

Of 380 PWID, 35.3% injected in the neck at least once in the past 6 months, among whom 71.6% reported it as their most common injection site, the most common injecting site after the arms (47%). Controlling for age, years injecting and injecting frequency, injecting heroin and methamphetamine two or more times per day and having sought injection assistance were associated with injecting in the neck [adjusted odds ratios (AOR): 2.12; 95% confidence intervals (CI): 1.27-3.53 and AOR: 2.65; 95% CI: 1.52-4.53 respectively].

DISCUSSION AND CONCLUSIONS

Injecting in the neck was very common among PWID in Tijuana and was associated with polydrug use and seeking injection assistance. Tailoring harm reduction education interventions for individuals who provide injection assistance ('hit doctors') may allow for the dissemination of safe injecting knowledge to reduce injection-related morbidity and mortality.

Polydrug Use and HIV Risk Among People Who Inject Heroin in Tijuana, Mexico: A Latent Class Analysis

BACKGROUND

Although most people who inject drugs (PWID) in Tijuana, Mexico, primarily inject heroin, injection and non-injection use of methamphetamine and cocaine is common. We examined patterns of polydrug use among heroin injectors to inform prevention and treatment of drug use and its health and social consequences.

METHODS

Participants were PWID residing in Tijuana, aged ≥18 years who reported heroin injection in the past six months and were recruited through respondent-driven sampling (n = 1,025). Latent class analysis was conducted to assign individuals to classes on a probabilistic basis, using four indicators of past six-month polydrug and polyroute use: cocaine injecting, cocaine smoking or snorting, methamphetamine injecting, and methamphetamine smoking or snorting. Latent class membership was regressed onto covariates in a multinomial logistic regression.

RESULTS

Latent class analyses testing 1, 2, 3, and 4 classes were fit, with the 3-class solution fitting best. Class 1 was defined by predominantly heroin use (50.2%, n = 515); class 2 by methamphetamine and heroin use (43.7%, n = 448), and class 3 by methamphetamine, cocaine, and heroin use (6.0%, n = 62). Bivariate and multivariate analyses indicated a group of methamphetamine and cocaine users that exhibited higher-risk sexual practices and lower heroin injecting frequency, and a group of methamphetamine users who were younger and more likely to be female.

CONCLUSIONS

Discrete subtypes of heroin PWID were identified based on methamphetamine and cocaine use patterns. These findings have identified subtypes of heroin injectors who require more tailored interventions to reduce the health and social harms of injecting drug use.

Prevalence and correlates of HIV and sexually transmitted infections among female sex workers and their non-commercial male partners in two Mexico-USA border cities

Female sex workers (FSWs) acquire HIV and other sexually transmitted infections (STIs) through unprotected sex with commercial and non-commercial (intimate) male partners. Little research has focused on FSWs' intimate relationships, within which condom use is rare. We sought to determine the prevalence and correlates of HIV/STIs within FSWs' intimate relationships in Northern Mexico. From 2010 to 2011, we conducted a cross-sectional survey of FSWs and their non-commercial male partners in Tijuana and Ciudad Juárez, Mexico. Eligible FSWs and their verified male partners were aged ≥18 years; FSWs reported lifetime use of heroin, cocaine, crack, or methamphetamine and recently exchanged sex (past month). Participants completed baseline questionnaires and testing for HIV, chlamydia, gonorrhea, and syphilis. We determined the prevalence and correlates of individuals' HIV/STI positivity using bivariate probit regression. Among 212 couples (n = 424), prevalence of HIV was 2.6 % (n = 11). Forty-two (9.9 %) tested positive for any HIV/STIs, which was more prevalent among women than men (12.7 % vs. 7.1 %, p < 0.05). FSWs with regular sex work clients were less likely to test positive for HIV/STIs than those without regular clients. Similarly, male partners of FSWs who had regular clients were 9 % less likely to have HIV/STIs. Higher sexual decision-making power was protective against HIV/STIs for women. Men who recently used methamphetamine or reported perpetrating any conflict within steady relationships were more likely to test positive for HIV/STIs. Within FSWs' intimate relationships in two Mexican-US border cities, nearly one in ten partners tested positive for HIV/STIs. Couple-based prevention interventions should recognize how intimate relationship factors and social contexts influence HIV/STI vulnerability.

Cross-border activities and association with current methamphetamine use among Chinese injection drug users (IDUs) in a China-Myanmar border region

BACKGROUND

Methamphetamine has become one of the most widely used illicit substances in the world. We measured the prevalence and identified the correlates of methamphetamine use amongst current injection drug users (IDUs) in a China-Myanmar border region.

METHODS

A cross-sectional survey including interviews and serological testing was conducted in 2012. Chinese IDUs who had injected within the past six months and aged ≥ 18 years were recruited using respondent-driven sampling (RDS). Logistic regression indentified factors associated with current methamphetamine use.

RESULTS

Among 370 IDUs recruited, prevalence of lifetime and current methamphetamine use was 84.2% and 75.2% respectively. Amongst 293 current users, 18.1% ever purchased methamphetamine from Myanmar while 8.9% ever used it there during the past 6 months. IDUs who had cross-border activities, including purchasing drugs (AOR: 1.20; 95% CI: 1.10, 1.31) and visiting family/friends, doing business or odd jobs in Myanmar (AOR: 1.13; 95% CI: 1.02, 1.24) were more likely to use methamphetamine in the past six months. Other factors independently associated with current methamphetamine use included being younger (aged  ≤ 25 years, AOR: 1.24; 95% CI: 1.09, 1.41), being syphilis positive (AOR: 1.17; 95% CI: 1.03, 1.33), having used previously self-used needle/syringe (AOR: 1.20; 95% CI: 1.08, 1.34) and recently received prevention services (AOR: 1.15; 95% CI: 1.04, 1.28).

CONCLUSION

Methamphetamine has become another major drug of use and poses the serious concern among injecting drug users living in the China/Myanmar border region. The bi-national cooperation is urgently needed to develop targeted effective intervention strategies.

Evaluating the impact of Mexico's drug policy reforms on people who inject drugs in Tijuana, B.C., Mexico, and San Diego, CA, United States: a binational mixed methods research agenda

Background

Policymakers and researchers seek answers to how liberalized drug policies affect people who inject drugs (PWID). In response to concerns about the failing “war on drugs,” Mexico recently implemented drug policy reforms that partially decriminalized possession of small amounts of drugs for personal use while promoting drug treatment. Recognizing important epidemiologic, policy, and socioeconomic differences between the United States—where possession of any psychoactive drugs without a prescription remains illegal—and Mexico—where possession of small quantities for personal use was partially decriminalized, we sought to assess changes over time in knowledge, attitudes, behaviors, and infectious disease profiles among PWID in the adjacent border cities of San Diego, CA, USA, and Tijuana, Baja California, Mexico.

Methods

Based on extensive binational experience and collaboration, from 2012–2014 we initiated two parallel, prospective, mixed methods studies: Proyecto El Cuete IV in Tijuana (n = 785) and the STAHR II Study in San Diego (n = 575). Methods for sampling, recruitment, and data collection were designed to be compatible in both studies. All participants completed quantitative behavioral and geographic assessments and serological testing (HIV in both studies; hepatitis C virus and tuberculosis in STAHR II) at baseline and four semi-annual follow-up visits. Between follow-up assessment visits, subsets of participants completed qualitative interviews to explore contextual factors relating to study aims and other emergent phenomena. Planned analyses include descriptive and inferential statistics for quantitative data, content analysis and other mixed-methods approaches for qualitative data, and phylogenetic analysis of HIV-positive samples to understand cross-border transmission dynamics.

Results

Investigators and research staff shared preliminary findings across studies to provide feedback on instruments and insights regarding local phenomena. As a result, recruitment and data collection procedures have been implemented successfully, demonstrating the importance of binational collaboration in evaluating the impact of structural-level drug policy reforms on the behaviors, health, and wellbeing of PWID across an international border.

Conclusions

Our prospective, mixed methods approach allows each study to be responsive to emerging phenomena within local contexts while regular collaboration promotes sharing insights across studies. The strengths and limitations of this approach may serve as a guide for other evaluations of harm reduction policies internationally.

Individual, interpersonal, and social-structural correlates of involuntary sex exchange among female sex workers in two Mexico-U.S. border cities

BACKGROUND

To investigate individual, interpersonal, and social-structural factors associated with involuntary sex exchange among female sex workers (FSWs) along the Mexico-U.S. border.

METHODS

In 2010 to 2011, 214 FSWs from Tijuana (n = 106) and Ciudad Juarez (n = 108) aged ≥ 18 years who reported lifetime use of heroin, cocaine, crack, or methamphetamine, having a stable partner, and having sold/traded sex in the past month completed quantitative surveys and HIV/sexually transmitted infection testing. Logistic regression was used to identify correlates of involuntary sex exchange among FSWs.

RESULTS

Of 214 FSWs, 31 (14.5%) reported involuntary sex exchange These women were younger at sex industry entry [adjusted odds ratio (AOR): 0.84/1-year increase, 95% confidence interval (CI): 0.72 to 0.97] and were significantly more likely to service clients whom they perceived to be HIV/sexually transmitted infection-infected (AOR: 12.41, 95% CI: 3.15 to 48.91). In addition, they were more likely to have clients who used drugs (AOR: 7.88, 95% CI: 1.52 to 41.00), report poor working conditions (AOR: 3.27, 95% CI: 1.03 to 10.31), and report a history of rape (AOR: 4.46, 95% CI: 1.43 to 13.91).

CONCLUSIONS

Involuntary sex exchange is disproportionate among FSWs who begin to exchange sex at a younger age, and these women experience elevated risk of violence and HIV/STIs related to their clients' behaviors and their working conditions. These data suggest the critical need for evidence-based approaches to preventing sexual exploitation of women and girls and to reducing harm among current sex workers. Multilevel interventions for all females who exchange sex and their clients that target interpersonal and social-structural risks (eg, measures to improve safety and reduce exploitation within the workplace) are needed.

Border crossing to inject drugs in Mexico among injection drug users in San Diego, California

We examined correlates of ever injecting drugs in Mexico among residents of San Diego, California. From 2007 to 2010, injecting drug users (IDUs) in San Diego underwent an interviewer-administered survey. Logistic regression identified correlates of injection drug use in Mexico. Of 302 IDUs, 38% were Hispanic, 72% male and median age was 37; 27% ever injected in Mexico; 43% reported distributive syringe sharing there. Factors independently associated with ever injecting drugs in Mexico included being younger at first injection, injecting heroin, distributive syringe sharing at least half of the time, and transporting drugs over the last 6 months. One-quarter of IDUs reported ever injecting drugs in Mexico, among whom syringe sharing was common, suggesting possible mixing between IDUs in the Mexico-US border region. Prospective studies should monitor trends in cross-border drug use in light of recent Mexican drug policy reforms partially decriminalizing drug possession.

Male injection drug users try new drugs following U.S. deportation to Tijuana, Mexico

BACKGROUND

Among male injection drug users (IDUs) in Tijuana, Mexico, U.S. deportation is associated with HIV transmission. Changing drug use behaviors following deportation, including the use of new drugs, may increase HIV risk but are understudied. We identify correlates of trying new drugs following male IDUs' most recent U.S. deportation to Mexico.

METHODS

In 2010, we recruited 328 deported male IDUs in Tijuana, Mexico. Questionnaires collected retrospective data on drug use and other HIV risk behaviors throughout migratory events. Logistic regression identified correlates of trying new drugs/combinations following their most recent deportations. Informed consent was obtained from all participants.

RESULTS

Nearly one in six men (n=52, 16%) tried new drugs following their most recent deportation, including heroin (n=31), methamphetamine (n=5), and heroin/methamphetamine combined (n=17). Trying new drugs following deportation was independently associated with U.S. incarceration (adjusted odds ratio [AOR]=3.96; 95% confidence interval [C.I.] 1.78, 8.84), increasing numbers of U.S. deportations (AOR=1.11 per deportation; C.I. 1.03, 1.20), feeling sad following deportation (AOR 2.69; C.I. 1.41, 5.14), and perceiving that one's current lifestyle increases HIV/AIDS risk (AOR 3.91; C.I. 2.05, 7.44).

CONCLUSIONS

Trying new drugs following U.S. deportation may be related to the unique contexts and stressors experienced by drug-abusing migrants as they attempt to reestablish their lives in Mexico. Findings imply an unmet need for health and social programs to alleviate pre- and post-deportation stressors faced by undocumented and return migrants in the U.S.-Mexico context.

"Over here, it's just drugs, women and all the madness": The HIV risk environment of clients of female sex workers in Tijuana, Mexico

HIV vulnerability depends upon social context. Based on broader debates in social epidemiology, political economy, and sociology of health, Rhodes' (2002) "risk environment" framework provides one heuristic for understanding how contextual features influence HIV risk, through different types of environmental factors (social, economic, policy, and physical) which interact at different levels of influence (micro, macro). Few data are available on the "risk environment" of male clients of female sex workers (FSWs); such men represent a potential "bridge" for transmission of HIV and other sexually transmitted infections from high- to low-prevalence populations. Using in-depth interviews (n = 30), we describe the HIV risk environment of male clients in Tijuana, Mexico, where disproportionately high HIV prevalence has been reported among FSWs and their clients. A number of environmental themes influence risky sex with FSWs and the interplay between individual agency and structural forces: social isolation and the search for intimacy; meanings and identities ascribed to Tijuana's Zona Roja (red light district) as a risky place; social relationships in the Zona Roja; and economic roles. Our findings suggest that clients' behaviors are deeply embedded in the local context. Using the HIV "risk environment" as our analytic lens, we illustrate how clients' HIV risks are shaped by physical, social, economic, and political factors. The linkages between these and the interplay between structural- and individual-level experiences support theories that view structure as both enabling as well as constraining. We discuss how the "embeddedness" of clients' experiences warrants the use of environmental interventions that address the circumstances contributing to HIV risk at multiple levels.

Crystal methamphetamine use among female street-based sex workers: Moving beyond individual-focused interventions

Given growing concern of the sexual risks associated with crystal methamphetamine use and the dearth of research characterizing the use of methamphetamine among street-based sex workers (FSWs), this study aimed to characterize the prevalence and individual, social, and structural contexts of crystal methamphetamine use among FSWs in a Canadian setting. Drawing on data from a prospective cohort, we constructed multivariate logistic models to examine independent correlates of crystal methamphetamine among FSWs over a two-year follow-up period using generalized estimating equations. Of a total of 255 street-based FSWs, 78 (32%) reported lifetime crystal methamphetamine use and 24% used crystal methamphetamine during the two-year follow-up period, with no significant associations between methamphetamine use and sexual risk patterns. In a final multivariate GEE model, FSWs who used crystal methamphetamine had a higher proportional odds of dual heroin injection (adjOR=2.98, 95%CI: 1.35-5.22), having a primary male sex partner who procures drugs for them (adjOR=1.79, 95%CI: 1.02-3.14), and working (adjOR=1.62, 95%CI: 1.04-2.65) and living (adjOR=1.41, 95%CI: 1.07-1.99) in marginalized public spaces. The findings highlight the crucial need to move beyond the individual to gender-focused safer environment interventions that mediate the physical and social risk environment of crystal methamphetamine use among FSWs.

Pasa la voz (spread the word): using women's social networks for HIV education and testing

Pasa la Voz (spread the word) is a human immunodeficiency virus (HIV) prevention methodology inspired by respondent-driven sampling (RDS) that uses social networks to access hard-to-reach populations. As field testing showed the approach to be efficacious among at-risk women in West Texas and Southern New Mexico, we set out to evaluate the methodology in a Mexican context. A local community organization, Programa Compañeros, first implemented a traditional one-on-one outreach strategy using promotoras (outreach workers) in Ciudad Juarez, Mexico, from September 2005 to January 2006. This was followed by implementation of Pasa la Voz from February 2006 to January 2007. The percentage of women agreeing to be tested increased from 11.9% to 49.9%, and staff time declined from 22.70 hours to 3.68 hours per HIV test, comparing the one-on-one with the Pasa la Voz methodology, respectively. Pasa la Voz was successful at imparting a cost-savings prevention education program with significant increases in the number of at-risk women being tested for HIV.

Increased drug use and STI risk with injection drug use among HIV-seronegative heterosexual methamphetamine users

Methamphetamine (MA) use has been found to be associated with increased risk of HIV and sexually transmitted infections (STI) among men having sex with men, but it is unknown whether those who inject MA are at greater risk for these infections than those who administer MA by other routes. Furthermore, comparable data from heterosexual MA users are lacking. We investigated whether the HIV and STI risks of male and female heterosexual MA users who inject MA differ from those of comparable users who do not inject. Between 2001 and 2005, we interviewed 452 HIV-negative men and women aged 18 and older who had recently used MA and engaged in unprotected sex. Their mean age was 36.6 years; 68% were male; ethnicity was 49.4% Caucasian, 26.8% African-American, and 12.8% Hispanic. Logistic regression identified factors associated with injecting MA. Compared to non-IDU, IDU were more likely to: be Caucasian; be homeless; have used MA for a longer period and used more grams of MA in the last 30 days; have a history of felony conviction; and report a recent STI. HIV and STI prevention interventions should be tailored according to MA users' method of administration.

Survival sex work involvement among street-involved youth who use drugs in a Canadian setting

BACKGROUND

Drug users engaged in survival sex work are at heightened risk for drug- and sexual-related harms. We examined factors associated with survival sex work among street-involved youth in Vancouver, Canada.

METHODS

From September 2005 to November 2007, baseline data were collected for the At-Risk Youth Study (ARYS), a prospective cohort of street-recruited youth aged 14-26 who use illicit drugs. Using multiple logistic regression, we compared youth who reported exchanging sex for money, drugs etc. with those who did not.

RESULTS

The sample included 560 youth: median age 22; 179 (32%) female; 63 (11%) reporting recent survival sex work. Factors associated with survival sex work in multivariate analyses included non-injection crack use [adjusted odds ratio (AOR) = 3.45, 95% confidence interval (CI): 1.75-6.78], female gender (AOR = 3.02, 95% CI: 1.66-5.46), Aboriginal ethnicity (AOR = 2.35, 95% CI: 1.28-4.29) and crystal methamphetamine use (AOR = 2.02, 95% CI: 1.13-3.62). In subanalyses, the co-use of crack cocaine and methamphetamine was shown to be driving the association between methamphetamine and survival sex work.

CONCLUSIONS

This study demonstrates a positive interactive effect of dual stimulant use in elevating the odds of survival sex work among street youth who use drugs. Novel approaches to reduce the harms associated with survival sex work among street youth who use stimulants are needed.

A tale of two cities: Social and environmental influences shaping risk factors and protective behaviors in two Mexico-US border cities

The economic, social, cultural, and political milieus that influence HIV risk behaviors along the US-Mexico border are understudied. In an effort to appropriately inform interventions targeting structural influences, we compared injecting drug using populations living in two cities--Ciudad Juárez, Chihuahua and Tijuana, Baja California--situated on the Mexico-US border. These populations presented with similar demographic profiles, but differed significantly in terms of social and environmental influences that can influence both risk and protective factors (e.g., family drug use, migration, drug use patterns). We observed distinct behavioral and structural influences in these two border cities that will require tailored intervention strategies to reduce HIV transmission.

Polydrug use among IDUs in Tijuana, Mexico: correlates of methamphetamine use and route of administration by gender

Tijuana is situated on the Mexico-USA border adjacent to San Diego, CA, on a major drug trafficking route. Increased methamphetamine trafficking in recent years has created a local consumption market. We examined factors associated with methamphetamine use and routes of administration by gender among injection drug users (IDUs). From 2006-2007, IDUs > or =18 years old in Tijuana were recruited using respondent-driven sampling, interviewed, and tested for HIV, syphilis, and TB. Logistic regression was used to assess associations with methamphetamine use (past 6 months), stratified by gender. Among 1,056 participants, methamphetamine use was more commonly reported among females compared to males (80% vs. 68%, p < 0.01), particularly, methamphetamine smoking (57% vs. 34%; p < 0.01). Among females (N = 158), being aged >35 years (AOR, 0.2; 95% CI, 0.1-0.6) was associated with methamphetamine use. Among males (N = 898), being aged >35 years (AOR, 0.5; 95% CI, 0.3-0.6), homeless (AOR, 1.4 (0.9-2.2)), and ever reporting sex with another male (MSM; AOR, 1.9; 95% CI, 1.4-2.7) were associated with methamphetamine use. Among males, a history of MSM was associated with injection, while sex trade and >2 casual sex partners were associated with multiple routes of administration. HIV was higher among both males and females reporting injection as the only route of methamphetamine administration. Methamphetamine use is highly prevalent among IDUs in Tijuana, especially among females. Routes of administration differed by gender and subgroup which has important implications for tailoring harm reduction interventions and drug abuse treatment.

The color of meth: is it related to adverse health outcomes? An exploratory study in Tijuana, Mexico

In a study of injection drug users (IDUs) in Tijuana, Mexico, logistic regression identified factors associated with injection of colored vs. clear methamphetamine in the prior six months (N = 613). Colors injected most often were clear (50%), white (47%), yellow (2%), and pink (1%). IDUs injecting colored meth were more likely to experience recent abscesses (34%) compared to those injecting clear meth (24%; p = 0.008), an association that persisted after adjusting for confounders. Market characteristics, possibly relating to purity or adulterants, may be associated with abscesses among methamphetamine injectors. Further study is needed to confirm and determine the mechanism of this association to better inform prevention messages.

Policies and laws affecting Mexican-origin immigrant access and utilization of substance abuse treatment: obstacles to recovery and immigrant health

This article reports the results of a study carried out with 30 Mexican-origin immigrants in drug user treatment in the United States-Mexico Border city of El Paso, Texas during 2007. Qualitative, semi-structured interviews were implemented to assess the dynamic social and economic factors that affect the delivery and utilization of treatment services, with emphasis on the impact of recent immigration-related laws and policies. The research provides initial data for evidence-based intervention and reinforces the need for culturally and gender appropriate treatment services for poor immigrants and their families. The study's limitations are noted.