Prevalence and Correlates of Injecting with Visitors from the United States Among People Who Inject Drugs in Tijuana, Mexico.

Cross-border infectious disease transmission is a concern related to drug tourism from the U.S. to Mexico. We assessed this risk among people who inject drugs (PWID) in Tijuana, Mexico. We measured the prevalence and identified correlates of injecting with PWID visiting from the U.S. among PWID in Tijuana using univariable and multivariable logistic regression. Of 727 participants, 18.5% injected during the past 6 months in Mexico with U.S. PWID described mostly as friends (63%) or acquaintances (26%). Injecting with U.S. PWID was independently associated with higher education [adjusted odds ratio (aOR) = 1.13/year], deportation from the U.S. (aOR = 1.70), younger age at first injection (aOR = 0.96/year), more lifetime overdoses (aOR = 1.08), and, in the past 6 months, backloading (aOR = 4.00), syringe confiscation by the police (aOR = 3.02) and paying for sex (aOR = 2.98; all p-values < 0.05). Nearly one-fifth of PWID in Tijuana recently injected with U.S. PWID, and their reported risk behaviors could facilitate cross-border disease transmission.

Oral and vaginal HIV pre-exposure prophylaxis product attribute preferences among female sex workers in the Mexico-US border region.

To assess the potential uptake of HIV pre-exposure prophylaxis (PrEP) products among female sex workers (FSWs) vulnerable to HIV infection, we examined the influence of product attributes on willingness to use products among 271 HIV-negative FSWs in Tijuana and Ciudad Juarez, Mexico (2016-2017). Via five-point Likert scale ratings, participants indicated their willingness to use hypothetical products with six attributes: formulation (pill, gel, liquid, or ring), frequency of use (daily, on-demand, or monthly), cost per use (10 or 200 pesos), effectiveness (40% or 80%), side effects (none or mild), and access point (healthcare clinic or non-governmental organization). Conjoint analysis was used to determine the impact of attributes on product ratings and identify preferred product attributes. Multinomial logistic regression was used to identify factors associated with formulation preferences. In both cities, formulation and frequency of use had the greatest impact on ratings. Participants in Ciudad Juarez indicated a strong preference for oral pills, whereas participants in Tijuana indicated roughly equal preferences for oral pills and vaginal gels. Monthly product use was preferred in both cities. Compared to preferring oral pills (38%), preferring vaginal gels (28%) was associated with practicing vaginal lubrication (adjusted odds ratio = 2.08; 95% confidence interval: 1.07-4.04). Oral PrEP may be acceptable to many FSWs in Tijuana and Ciudad Juarez; however, continued development of behaviorally-congruent vaginal PrEP products may also facilitate uptake and ensure sufficient coverage.

Building the Case for Localized Approaches to HIV: Structural Conditions and Health System Capacity to Address the HIV/AIDS Epidemic in Six US Cities.

Since the discovery of the secondary preventive benefits of antiretroviral therapy, national and international governing bodies have called for countries to reach 90% diagnosis, ART engagement and viral suppression among people living with HIV/AIDS. The US HIV epidemic is dispersed primarily across large urban centers, each with different underlying epidemiological and structural features. We selected six US cities, including Atlanta, Baltimore, Los Angeles, Miami, New York, and Seattle, with the objective of demonstrating the breadth of epidemiological and structural differences affecting the HIV/AIDS response across the US. We synthesized current and publicly-available surveillance, legal statutes, entitlement and discretionary funding, and service location data for each city. The vast differences we observed in each domain reinforce disparities in access to HIV treatment and prevention, and necessitate targeted, localized strategies to optimize the limited resources available for each city's HIV/AIDS response.

The law on the streets: Evaluating the impact of Mexico's drug decriminalization reform on drug possession arrests in Tijuana, Mexico.

BACKGROUND: In 2009, Mexican Federal Government enacted "narcomenudeo" reforms decriminalizing possession of small amounts of drugs, delegating prosecution of retail drug sales to the state courts, and mandating treatment diversion for habitual drug users. There has been insufficient effort to formally assess the decriminalization policy's population-level impact, despite mounting interest in analagous reforms across the globe. METHODS: Using a dataset of municipal police incident reports, we examined patterns of drug possession, and violent and non-violent crime arrests between January 2009 and December 2014. A hierarchical panel data analysis with random effects was conducted to assess the impact of narcomenudeo's drug decriminalization provision. RESULTS: The reforms had no significant impact on the number of drug possession or violent crime arrests, after controlling for other variables (e.g. time trends, electoral cycles, and precinct-level socioeconomic factors). Time periods directly preceding local elections were observed to be statistically associated with elevated arrest volume. CONCLUSIONS: Analysis of police statistics parallel prior findings that Mexico's reform decriminalizing small amounts of drugs does not appear to have significantly shifted drug law enforcement in Tijuana. More research is required to fully understand the policy transformation process for drug decriminalization and other structural interventions in Mexico and similar regional and international efforts. Observed relationship between policing and political cycles echo associations in other settings whereby law-and-order activities increase during mayoral electoral campaigns.

Do law enforcement interactions reduce the initiation of injection drug use? An investigation in three North American settings.

BACKGROUND: The prevention of drug injecting is often cited as a justification for the deployment of law enforcement and for the continuation of drug criminalization policies. We sought to characterize the impact of law enforcement interactions on the risk that people who inject drugs (PWID) report assisting others with injection initiation in three North American countries. METHODS: Cross-sectional data from PWID participating in cohort studies in three cities (San Diego, USA; Tijuana, Mexico; Vancouver, Canada) were pooled (August 2014-December 2016). The dependent variable was defined as recently (i.e., past six months) providing injection initiation assistance; the primary independent variable was the frequency of recent law enforcement interactions, defined categorically (0 vs. 1 vs. 2-5 vs. ≥6). We employed multivariable logistic regression analyses to assess this relationship while controlling for potential confounders. RESULTS: Among 2122 participants, 87 (4.1%) reported recently providing injection initiation assistance, and 802 (37.8%) reported recent law enforcement interactions. Reporting either one or more than five recent interactions with law enforcement was not significantly associated with injection initiation assistance. Reporting 2-5 law enforcement interactions was associated with initiation assistance (Adjusted Odds Ratio=1.74, 95% Confidence Interval: 1.01-3.02). CONCLUSIONS: Reporting interactions with law enforcement was not associated with a reduced likelihood that PWID reported initiating others into injection drug use. Instead, we identified a positive association between reporting law enforcement interactions and injection initiation assistance among PWID in multiple settings. These findings raise concerns regarding the effectiveness of drug law enforcement to deter injection drug use initiation.

Measuring improvement in knowledge of drug policy reforms following a police education program in Tijuana, Mexico.

BACKGROUND: Mexico's 2009 "narcomenudeo reform" decriminalized small amounts of drugs, shifting some drug law enforcement to the states and mandating drug treatment diversion instead of incarceration. Data from Tijuana suggested limited implementation of this harm reduction-oriented policy. We studied whether a police education program (PEP) improved officers' drug and syringe policy knowledge, and aimed to identify participant characteristics associated with improvement of drug policy knowledge. METHODS: Pre- and post-training surveys were self-administered by municipal police officers to measure legal knowledge. Training impact was assessed through matched paired nominal data using McNemar's tests. Multivariable logistic regression was used to identify predictors of improved legal knowledge, as measured by officers' ability to identify conceptual legal provisions related to syringe possession and thresholds of drugs covered under the reform. RESULTS: Of 1750 respondents comparing pre- versus post training, officers reported significant improvement (p < 0.001) in their technical understanding of syringe possession (56 to 91%) and drug amounts decriminalized, including marijuana (9 to 52%), heroin (8 to 71%), and methamphetamine (7 to 70%). The training was associated with even greater success in improving conceptual legal knowledge for syringe possession (67 to 96%) (p < 0.001), marijuana (16 to 91%), heroin (11 to 91%), and methamphetamine (11 to 89%). In multivariable modeling, those with at least a high school education were more likely to exhibit improvement of conceptual legal knowledge of syringe possession (adjusted odds ratio [aOR] 2.6, 95% CI 1.4-3.2) and decriminalization for heroin (aOR 2.7, 95% CI 1.3-4.3), methamphetamine (aOR 2.2, 95% CI 1.4-3.2), and marijuana (aOR 2.5, 95% CI 1.6-4). CONCLUSIONS: Drug policy reform is often necessary, but not sufficient to achieve public health goals because of gaps in translating formal laws to policing practice. To close such gaps, PEP initiatives bundling occupational safety information with relevant legal content demonstrate clear promise. Our findings underscore additional efforts needed to raise technical knowledge of the law among personnel tasked with its enforcement. Police professionalization, including minimum educational standards, appear critical for aligning policing with harm reduction goals.

Mycobacterium tuberculosis infection among persons who inject drugs in San Diego, California.

BACKGROUND: Persons who inject drugs (PWID) might be at increased risk for Mycobacterium tuberculosis infection and reactivation of latent tuberculous infection (LTBI) due to their injection drug use. OBJECTIVES: To determine prevalence and correlates of M. tuberculosis infection among PWID in San Diego, California, USA. METHODS: PWID aged 18 years underwent standardized interviews and serologic testing using an interferon-gamma release assay (IGRA) for LTBI and rapid point-of-care assays for human immunodeficiency virus (HIV) and hepatitis C virus (HCV) infections. Independent correlates of M. tuberculosis infection were identified using multivariable log-binomial regression. RESULTS: A total of 500 participants met the eligibility criteria. The mean age was 43.2 years (standard deviation 11.6); most subjects were White (52%) or Hispanic (30.8%), and male (75%). Overall, 86.7% reported having ever traveled to Mexico. Prevalence of M. tuberculosis infection was 23.6%; 0.8% were co-infected with HIV and 81.7% were co-infected with HCV. Almost all participants (95%) had been previously tested for M. tuberculosis; 7.6% had been previously told they were infected. M. tuberculosis infection was independently associated with being Hispanic, having longer injection histories, testing HCV-positive, and correctly reporting that people with 'sleeping' TB cannot infect others. CONCLUSIONS: Strategies are needed to increase awareness about and treatment for M. tuberculosis infection among PWID in the US/Mexico border region.

Change in attitudes and knowledge of problem drug use and harm reduction among a community cohort in Kabul, Afghanistan.

This pre-post evaluation aimed to measure changes in knowledge and attitudes towards drug users among community representatives in Kabul, Afghanistan, over a period of expansion of harm reduction and drug dependence programming. A convenience sample of 160 professionals aged 18+ years completed interview questionnaires in 2007 and 2009. Views endorsing programme quality and the provision of condoms, infection counselling/testing and needle/syringe distribution increased significantly over the 2-year period. In 13 of 38 statements, there was a substantial (> 10%) change in agreement level, most commonly among men and medical professionals. Attitudes concerning support of drug users remained largely positive, with substantial attitude changes in some subgroups of the population. Further community education through the media and a more cohesive government drug policy may be needed to strengthen community support for harm reduction/drug treatment in Afghanistan.

The effectiveness of compulsory drug treatment: A systematic review.

BACKGROUND: Despite widespread implementation of compulsory treatment modalities for drug dependence, there has been no systematic evaluation of the scientific evidence on the effectiveness of compulsory drug treatment. METHODS: We conducted a systematic review of studies assessing the outcomes of compulsory treatment. We conducted a search in duplicate of all relevant peer-reviewed scientific literature evaluating compulsory treatment modalities. The following academic databases were searched: PubMed, PAIS International, Proquest, PsycINFO, Web of Science, Soc Abstracts, JSTOR, EBSCO/Academic Search Complete, REDALYC, SciELO Brazil. We also searched the Internet, and article reference lists, from database inception to July 15th, 2015. Eligibility criteria are as follows: peer-reviewed scientific studies presenting original data. Primary outcome of interest was post-treatment drug use. Secondary outcome of interest was post-treatment criminal recidivism. RESULTS: Of an initial 430 potential studies identified, nine quantitative studies met the inclusion criteria. Studies evaluated compulsory treatment options including drug detention facilities, short (i.e., 21-day) and long-term (i.e., 6 months) inpatient treatment, community-based treatment, group-based outpatient treatment, and prison-based treatment. Three studies (33%) reported no significant impacts of compulsory treatment compared with control interventions. Two studies (22%) found equivocal results but did not compare against a control condition. Two studies (22%) observed negative impacts of compulsory treatment on criminal recidivism. Two studies (22%) observed positive impacts of compulsory inpatient treatment on criminal recidivism and drug use. CONCLUSION: There is limited scientific literature evaluating compulsory drug treatment. Evidence does not, on the whole, suggest improved outcomes related to compulsory treatment approaches, with some studies suggesting potential harms. Given the potential for human rights abuses within compulsory treatment settings, non-compulsory treatment modalities should be prioritized by policymakers seeking to reduce drug-related harms.

Change in attitudes and knowledge of problem drug use and harm reduction among a community cohort in Kabul, Afghanistan

هذا التقييم لما قبل ومابعد تطبيق البرنامج يهدف الى قياس التغيرات التي طرأت على المعارف والاتجاهات تجاه متعاطي المخدرات لدي ممثلين عن المجتمع في كابول بافغانستان خلال فتره من فترات التوسع في تطبيق برنامج لمعالجه ادمان المخدرات والحد من اضرارها فقد قامت عينه ملائمه تضم 160 مهنيا اعمارهم 18 سنه فما فوق بملء استبيانات مقابله في عامي 2007 و 2009 فتبين ان الآراء المؤيدة لجودة البرنامج ولتوفير الواقي الذكري وتقديم المشورة والاختبارات الخاصة بالعدوي وتوزيع الابر والمحاقن قد ازدادت زيادة ملحوظة خلال هذين العامين وكان هناك تغير جوهري في مستوي القبول ( اكثر من 10%)في 13 بيانا من اصل 38 لاسيما لدي الرجال واصحاب المهن الطبيه المتعلقه بدعم متعاطي المخدرات ايجابيه الى حد كبير مع تغيرات كبيره في مواقف بعض المجموعات السكانيه الفرعيه ربما تكون هناك حاجة الى مزيد من تثقيف المجتمع عن طريق وسائل الاعلام والى سياسه حكوميه اكثر تماسكا بشأن المخدرات تعزز دعم المجتمع لمعالجة تعاطي المخدرات والحد من اضرارها في افغانستان

La presente evaluation pre-post visait a mesurer ['acquisition de connaissances et les changements d'attitudes a I'egard des toxicomanes parmi les representants d'une communaute a Kaboul [Afghanistan]au cours d'une periode d'elargissement des programmes de reduction des effets nocifs et de traitement de la clependance aux drogues.Un echantillon de commodite de 160 professionnels ages de plus de 18 ans a rempli des questionnaires dans le cadre d'entretiens en 2007 et en 2009.Les opinions au sujet de ['application de programmes de qualite et de la fourniture de preservatifs,du conseil et du depistage en matiere defections,ainsi que de la distribution d/aiguilles/de seringues se sont considerablement ameliorees au cours de ces deux annees.Dans 13 des 38 declarations,on a pu noter un changement notable [>10 %]dans le niveau d'acceptation,le plus souvent parmi les hommes et les professionnels de sante.Les attitudes concernant le soutien a apporter aux toxicomanes sont restees positives dans une large mesure,avec des changements d'attitude notables dans certains sous-groupes de la population.Une education plus poussee des communautes par le biais des medias et des politiques gouvernementales de lutte contre la drogue plus coherentes sont necessaires pour renforcer le soutien communautaire a la reduction des effets nocifs/au traitement des toxicomanies en Afghanistan

This pre-post evaluation aimed to measure changes in knowledge and attitudes towards drug users among community representatives in Kabul,Afghanistan,over a period of expansion of harm reduction and drug dependence programming.A convenience sample of 160 professionals aged 18+ years completed interview questionnaires in 2007 and 2009.Views endorsing programme quality and the provision of condoms,infection counselling/testing and needle/syringe distribution increased significantly over the 2-year period.In 13 of 38 statements,there was a substantial [>10%]change in agreement level,most commonly among men and medical professionals.Attitudes concerning support of drug users remained largely positive,with substantial attitude changes in some subgroups of the population.further community education through the media and a more cohesive government drug policy may be needed to strengthen community support for harm reduction/drug treatment in Afghanistan

Police bribery and access to methadone maintenance therapy within the context of drug policy reform in Tijuana, Mexico.

AIMS: In 2009, Mexico passed legislation to decriminalize drug possession and improve access to addiction treatment. We undertook research to assess the implementation of the reform among a cohort of people who inject drugs (PWID) in Tijuana. This study specifically sought to determine whether discretionary policing practices like extortion impact access to methadone maintenance therapy (MMT) in Tijuana, a city characterized by high levels of drug-related harms. METHODS: Generalized estimating equation analyses were used to construct longitudinal confounding models to determine the association between paying a police bribe and MMT enrolment among PWID in Tijuana enrolled in a prospective cohort study. Outcome of interest was MMT enrolment in the past six months. Data on police interactions and MMT enrolment were also obtained. RESULTS: Between October, 2011 and September, 2013, 637 participants provided 1825 observations, with 143 (7.8%) reports of MMT enrolment during the study period. In a final confounding model, recently reporting being forced to pay a bribe to police was significantly associated with an increased likelihood of accessing MMT (adjusted odds ratio=1.69, 95% confidence interval: 1.02-2.81, p=0.043). However, in 56 (39.2%) cases, MMT enrolment ceased within six months. The majority of participant responses cited the fact that MMT was too expensive (69.1%). DISCUSSION: Levels of MMT access were low. PWID who experienced police extortion were more likely to access MMT at baseline, though this association decreased during the study period. Coupled with the costs of MMT, this may compromise MMT retention among PWID.

Successes and gaps in uptake of regular, voluntary HIV testing for hidden street- and off-street sex workers in Vancouver, Canada.

Despite evidence globally of the heavy HIV burden among sex workers (SWs) as well as other poor health outcomes, including violence, SWs are often excluded from accessing voluntary, confidential and non-coercive health services, including HIV prevention, treatment, care and support. This study therefore assessed the prevalence and association with regular HIV testing among street- and off-street SWs in Vancouver, Canada. Cross-sectional baseline data were used from a longitudinal cohort known as "An Evaluation of Sex Worker's Health Access" (AESHA; January 2010-July 2012). This cohort included youth and adult SWs (aged 14+ years). We used multivariable logistic regression to assess the relationship between explanatory variables and having a recent HIV test (in the last year). Of the 435 seronegative SWs included, 67.1% reported having a recent HIV test. In multivariable logistic regression analysis, having a recent HIV test remained significantly independently associated with elevated odds of inconsistent condom use with clients [adjusted (multivariable) odds ratios, AOR: 2.59, 95% confidence intervals [95% CIs]: 1.17-5.78], injecting drugs (AOR: 2.33, 95% CIs: 1.17-4.18) and contact with a mobile HIV prevention programme (AOR: 1.76, 95% CIs: 1.09-2.84) within the last six months. Reduced odds of having a recent HIV test was also significantly associated with being a migrant/new immigrant to Canada (AOR: 0.33, 95% CIs: 0.19-0.56) and having a language barrier to health care access (AOR: 0.26, 95% CIs: 0.09-0.73). Our results highlight successes of reaching SWs at high risk of HIV through drug and sexual pathways. To maximize the effectiveness of including HIV testing as part of comprehensive HIV prevention and care to SWs, increased mobile outreach and safer-environment interventions that facilitate access to voluntary, confidential and non-coercive HIV testing remain a critical priority, in addition to culturally safe services with language support.

Dose-response association between salivary cotinine levels and Mycobacterium tuberculosis infection.

SETTING: Tijuana, Mexico. OBJECTIVE: To describe the association between salivary cotinine levels and interferon-gamma (IFN-γ) release assay results. DESIGN: We conducted a cross-sectional study among injection drug users. Salivary cotinine levels were measured using NicAlert, a semi-quantitative dipstick assay. QuantiFERON©-TB Gold In-Tube (QFT-GIT) was used to determine Mycobacterium tuberculosis infection. RESULTS: Among 234 participants, the prevalence of QFT-GIT positivity for NicAlert cotinine categories 0 (non-smoking), 1 (second-hand smoke exposure or low-level smoking) and 26 (regular smoking) were respectively 42.1%, 46.4% and 65.2% (Ptrend 0.012). We found increasing trends in QFT-GIT positivity (Ptrend 0.003) and IFN-γ concentrations (Spearman's r 0.200, P 0.002) across cotinine levels 0 to 6. In multivariable log-binomial regression models adjusted for education, cotinine levels were not associated with QFT-GIT positivity when included as smoking categories (1 and 26 vs. 0), but were independently associated with QFT-GIT positivity when included as an ordinal variable (prevalence ratio 1.09 per 1 cotinine level, 95%CI 1.021.16). CONCLUSION: Our findings suggest that a dose-response relationship exists between tobacco smoke exposure and M. tuberculosis infection. Longitudinal studies that use biochemical measures for smoking status are needed to confirm our findings.

The longitudinal association of venue stability with consistent condom use among female sex workers in two Mexico-USA border cities.

We examined the relationship between venue stability and consistent condom use (CCU) among female sex workers who inject drugs (FSW-IDUs; n = 584) and were enrolled in a behavioural intervention in two Mexico-USA border cities. Using a generalized estimating equation approach stratified by client type and city, we found venue stability affected CCU. In Tijuana, operating primarily indoors was significantly associated with a four-fold increase in the odds of CCU among regular clients (odds ratio [OR]: 3.77, 95% confidence interval [CI]: 1.44, 9.89), and a seven-fold increase among casual clients (OR: 7.18, 95% CI: 2.32, 22.21), relative to FSW-IDUs spending equal time between indoor and outdoor sex work venues. In Ciudad Juarez, the trajectory of CCU increased over time and was highest among those operating primarily indoors. Results from this analysis highlight the importance of considering local mobility, including venue type and venue stability, as these characteristics jointly influence HIV risk behaviours.

Condom use among female sex workers and their non-commercial partners: effects of a sexual risk intervention in two Mexican cities.

The purpose of this study was to examine whether a brief behavioural intervention promoting condom use among female sex workers (FSWs) and their clients had the added benefit of increasing condom use among FSWs and their steady, non-commercial partners (e.g. husbands, boyfriends). Participants were 362 FSWs, aged ≥18 years, living in Tijuana or Ciudad Juarez, Mexico, who received a behavioural intervention to promote condom use with clients. Repeated-measures negative binomial regression was used to assess FSWs' condom use with steady partners versus clients across time. Results showed that FSWs engaged in unprotected sex with steady partners more than with their clients, and that the intervention changed FSWs' condom use with clients but not their steady partners. HIV-prevention interventions for FSWs should promote consistent condom use across partner type. Targeting couples rather than individuals may also be necessary.

Longitudinal determinants of consistent condom use by partner type among young injection drug users: the role of personal and partner characteristics.

We investigated the longitudinal influence of individual-, relationship- and social-level factors on condom use by partner type among young injections drug users (IDUs) enrolled in the Collaborative Injection Drug Users Study-III/Drug Users Intervention Trial (CIDUS-III/DUIT) from 2002 to 2004. Based on longitudinal analysis using generalized estimating equations (GEE), consistent condom use with main partners was more commonly reported among males and those with greater self-efficacy for condom use; main partner's desire for pregnancy and needle sharing were negatively associated with consistent condom use. Among those with casual partners, having fewer sex partners was associated with consistent condom use. Positive attitudes toward condom use and partner norms supporting condom use were associated with greater consistent condom use with both partner types. These findings suggest that intervention strategies targeting individual- and partner-level factors may provide avenues for intervening upon sexual risks among young IDUs.

Risk factors associated with chlamydia and gonorrhoea infection among female sex workers in two Mexico-USA border cities.

Female sex workers (FSWs) aged ≥18 years without known HIV infection living in Tijuana and Ciudad Juarez, Mexico who had recent unprotected sex with clients underwent interviews and testing for chlamydia and gonorrhoea using nucleic acid amplification. Correlates of each infection were identified with logistic regression. Among 798 FSWs, prevalence of chlamydia and gonorrhoea was 13.0% and 6.4%, respectively. Factors independently associated with chlamydia were younger age, working in Tijuana versus Ciudad Juarez and recent methamphetamine injection. Factors independently associated with gonorrhoea were working in Tijuana versus Ciudad Juarez, using illegal drugs before or during sex, and having a recent male partner who injects drugs. Chlamydia and gonorrhoea infection were more closely associated with FSWs' drug use behaviours and that of their sexual partners than with sexual behaviours. Prevention should focus on subgroups of FSWs and their partners who use methamphetamine and who inject drugs.

Targeted screening and treatment for latent tuberculosis infection using QuantiFERON-TB Gold is cost-effective in Mexico.

OBJECTIVE: To assess the cost-effectiveness of screening for latent tuberculosis infection (LTBI) using a commercially available detection test and treating individuals at high risk for human immunodeficiency virus (HIV) infection in a middle-income country. DESIGN: We developed a Markov model to evaluate the cost per LTBI case detected, TB case averted and quality-adjusted life year (QALY) gained for a cohort of 1000 individuals at high risk for HIV infection over 20 years. Baseline model inputs for LTBI prevalence were obtained from published literature and cross-sectional data from tuberculosis (TB) screening using QuantiFERON-TB Gold In-Tube (QFT-GIT) testing among sex workers and illicit drug users at high risk for HIV recruited through street outreach in Tijuana, Mexico. Costs are reported in 2007 US dollars. Future costs and QALYs were discounted at 3% per year. Sensitivity analyses were performed to evaluate model robustness. RESULTS: Over 20 years, we estimate the program would prevent 78 cases of active TB and 55 TB-related deaths. The incremental cost per case of LTBI detected was US$730, cost per active TB averted was US$529 and cost per QALY gained was US$108. CONCLUSIONS: In settings of endemic TB and escalating HIV incidence, targeting LTBI screening and treatment among high-risk groups may be highly cost-effective.

Prevalence and structural correlates of gender based violence among a prospective cohort of female sex workers.

OBJECTIVE: To examine the prevalence and structural correlates of gender based violence against female sex workers in an environment of criminalised prostitution. DESIGN: Prospective observational study. SETTING: Vancouver, Canada during 2006-8. PARTICIPANTS: Female sex workers 14 years of age or older (inclusive of transgender women) who used illicit drugs (excluding marijuana) and engaged in street level sex work. MAIN OUTCOME MEASURE: Self reported gender based violence. RESULTS: Of 267 female sex workers invited to participate, 251 women returned to the study office and consented to participate (response rate of 94%). Analyses were based on 237 female sex workers who completed a baseline visit and at least one follow-up visit. Of these 237 female sex workers, 57% experienced gender based violence over an 18 month follow-up period. In multivariate models adjusted for individual and interpersonal risk practices, the following structural factors were independently correlated with violence against female sex workers: homelessness (adjusted odds ratio for physical violence (aOR(physicalviolence)) 2.14, 95% confidence interval 1.34 to 3.43; adjusted odds ratio for rape (aOR(rape)) 1.73, 1.09 to 3.12); inability to access drug treatment (adjusted odds ratio for client violence (aOR(clientviolence)) 2.13, 1.26 to 3.62; aOR(physicalviolence) 1.96, 1.03 to 3.43); servicing clients in cars or public spaces (aOR(clientviolence) 1.50, 1.08 to 2.57); prior assault by police (aOR(clientviolence) 3.45, 1.98 to 6.02; aOR(rape) 2.61, 1.32 to 5.16); confiscation of drug use paraphernalia by police without arrest (aOR(physicalviolence) 1.50, 1.02 to 2.41); and moving working areas away from main streets owing to policing (aOR(clientviolence) 2.13, 1.26 to 3.62). CONCLUSIONS: Our results demonstrate an alarming prevalence of gender based violence against female sex workers. The structural factors of criminalisation, homelessness, and poor availability of drug treatment independently correlated with gender based violence against street based female sex workers. Socio-legal policy reforms, improved access to housing and drug treatment, and scale up of violence prevention efforts, including police-sex worker partnerships, will be crucial to stemming violence against female sex workers.

High prevalence of latent tuberculosis infection among injection drug users in Tijuana, Mexico.

BACKGROUND: We studied prevalence and correlates of latent tuberculosis infection (LTBI) among injection drug users (IDUs) in Tijuana, Mexico, where tuberculosis (TB) is endemic. METHODS: IDUs aged > or =18 years were recruited via respondent-driven sampling (RDS) and underwent standardized interviews, human immunodeficiency virus (HIV) antibody testing and LTBI screening using Quanti-FERON((R))-TB Gold In-Tube, a whole-blood interferon-gamma release assay (IGRA). LTBI prevalence was estimated and correlates were identified using RDS-weighted logistic regression. RESULTS: Of 1020 IDUs, 681 (67%) tested IGRA-positive and 44 (4%) tested HIV-positive. Mean age was 37 years, 88% were male and 98% were Mexican-born. IGRA positivity was associated with recruitment nearest the US border (aOR 1.64, 95%CI 1.09-2.48), increasing years of injection (aOR 1.20/5 years, 95%CI 1.07-1.34), and years lived in Tijuana (aOR 1.10/5 years, 95%CI 1.03-1.18). Speaking some English (aOR 0.38, 95%CI 0.25-0.57) and injecting most often at home in the past 6 months (aOR 0.68, 95%CI 0.45-0.99) were inversely associated with IGRA positivity. DISCUSSION: Increased LTBI prevalence among IDUs in Tijuana appears to be associated with greater drug involvement. Given the high risk for HIV infection among Tijuana's IDUs, interventions are urgently needed to prevent HIV infection and treat LTBI among IDUs before these epidemics collide.