Objective-We examined correlates of HIV infection among injection drug users (IDUs) in Tijuana, Mexico, a city bordering the United States, which is situated on major migration and drug trafficking routes.Methods-IDUs aged ≥18 years were recruited using respondent-driven sampling. Participants underwent antibody testing for HIV and syphilis and structured interviews. Weighted logistic regression identified correlates of HIV infection.Results-Of 1056 IDUs, the median age was 37 years, 86% were male, and 76% were migrants. HIV prevalence was higher in female participants than in male participants (8% vs. 3%; P = 0.01). Most IDUs testing HIV-positive were previously unaware of their serostatus (93%). IDUs reported injecting with a median of 2 people in the prior 6 months and had been arrested for having injection stigmata (ie, "track-marks") a median of 3 times. Factors independently associated with HIV infection were being female, syphilis titers consistent with active infection, larger numbers of recent injection partners, living in Tijuana for a shorter duration, and being arrested for having track-marks.Conclusions-Individual, social, and environmental factors were independently associated with HIV infection among IDUs in Tijuana. These findings suggest the need to intervene not solely on individual risk behaviors but on social processes that drive these behaviors, including problematic policing practices. Policing practices may have a significant impact on IDUs' ability to adhere to safe injection practices, thereby influencing their risk of acquiring HIV. Qualitative evidence shows that local policing practices influence how, where, and under what circumstances IDUs obtain and use injection equipment. 28,[30][31][32][33][34] Disruptions to IDUs' risk reduction practices and engagement in HIV risk behavior have been linked to high-visibility policing and fear of arrest or detainment, 30 which exacerbates withdrawal symptoms. Quantitative studies report that aggressive policing practices are associated with higher levels of needle sharing [35][36][37][38] and lower utilization of syringe exchange programs (SEPs). 39,40 In an ecologic study of the macrolegal environment in 89 metropolitan areas in the United States, Friedman and colleagues 41 showed that higher levels of legal repressiveness were positively associated with HIV prevalence among IDUs. Studies are lacking to determine how such effects interplay alongside individual and social network factors. KeywordsMobility is emerging as an important risk factor in the transmission dynamics of communicable diseases, including HIV. [42][43][44][45] Migration and mobility are associated with family separation, disintegration of social networks, sudden changes in the cultural environment, homelessness, poverty, social isolation, and a greater sense of anonymity, which may enable riskier behaviors. [46][47][48][49][50] In one study, social pressures, including legal problems, entering drug treatment, and the It is legal to purchase or carry syringes without ...

Objective To examine efficacy of a brief behavioral intervention to promote condom use among female sex workers (FSWs) in two Mexico-U.S. border cities. Methods 924 FSWs aged ≥18 years without known HIV infection living in Tijuana and Ciudad Juarez having recent unprotected sex with clients were randomized to a 30 minute behavioral intervention integrating motivational interviewing and principles of behavior change, or a didactic control condition. At baseline and six months, women underwent interviews and testing for HIV, syphilis, gonorrhea and chlamydia. Results Comparing intervention versus control groups, we observed a 40% decline in cumulative STI incidence (p=0.049). Incidence density for the intervention vs. control was 13.8 vs 24.92 per 100 person years (py) for STIs combined (p=0.034), and 0 vs. 2.01 per 100 py for HIV (p<0.001), with concomitant increases in total numbers and percentages of protected sex acts and decreases in total numbers of unprotected sex acts with clients (p<0.05). Conclusions This brief behavioral intervention shows promise in reducing HIV/STI risk behaviors among FSWs in two Mexican-U.S border cities, and may be transferable to other resource-constrained settings.

SummaryBackgroundPeople who inject drugs (PWID) experience a high prevalence of incarceration and might be at high risk of HIV and hepatitis C virus (HCV) infection during or after incarceration. We aimed to assess whether incarceration history elevates HIV or HCV acquisition risk among PWID.MethodsIn this systematic review and meta-analysis, we searched MEDLINE, Embase, and PsycINFO databases for studies in any language published from Jan 1, 2000 until June 13, 2017 assessing HIV or HCV incidence among PWID. We included studies that measured HIV or HCV incidence among community-recruited PWID. We included only studies reporting original results and excluded studies that evaluated incident infections by self-report. We contacted authors of cohort studies that met the inclusion or exclusion criteria, but that did not report on the outcomes of interest, to request data. We extracted and pooled data from the included studies using random-effects meta-analyses to quantify the associations between recent (past 3, 6, or 12 months or since last follow-up) or past incarceration and HIV or HCV acquisition (primary infection or reinfection) risk among PWID. We assessed the risk of bias of included studies using the Newcastle-Ottawa Scale. Between-study heterogeneity was evaluated using the I2 statistic and the P-value for heterogeneity.FindingsWe included published results from 20 studies and unpublished results from 21 studies. These studies originated from Australasia, western and eastern Europe, North and Latin America, and east and southeast Asia. Recent incarceration was associated with an 81% (relative risk [RR] 1·81, 95% CI 1·40–2·34) increase in HIV acquisition risk, with moderate heterogeneity between studies (I2=63·5%; p=0·001), and a 62% (RR 1·62, 95% CI 1·28–2·05) increase in HCV acquisition risk, also with moderate heterogeneity between studies (I2=57·3%; p=0·002). Past incarceration was associated with a 25% increase in HIV (RR 1·25, 95% CI 0·94–1·65) and a 21% increase in HCV (1·21, 1·02–1·43) acquisition risk.InterpretationIncarceration is associated with substantial short-term increases in HIV and HCV acquisition risk among PWID and could be a significant driver of HCV and HIV transmission among PWID. These findings support the need for developing novel interventions to minimise the risk of HCV and HIV acquisition, including addressing structural risks associated with drug laws and excessive incarceration of PWID.FundingEngineering and Physical Sciences Research Council, National Institute for Health Research, National Institutes of Health.

BackgroundWe evaluated brief combination interventions to simultaneously reduce sexual and injection risks among female sex workers who inject drugs (FSW-IDUs) in Tijuana and Ciudad Juarez, Mexico during 2008–2010, when harm reduction coverage was expanding rapidly in Tijuana, but less so in Juarez.MethodsFSW-IDUs ≥18 years reporting sharing injection equipment and unprotected sex with clients within the last month participated in a randomized factorial trial comparing four brief, single-session conditions combining either an interactive or didactic version of a sexual risk intervention to promote safer sex in the context of drug use, and an injection risk intervention to reduce sharing of needles/injection paraphernalia. Women underwent quarterly interviews and testing for HIV, syphilis, gonorrhea, Chlamydia and Trichomonas, blinding interviewers and assessors to assignment. Poisson regression with robust variance estimation and repeated measures ordinal logistic regression examined effects on combined HIV/STI incidence and receptive needle sharing frequency.FindingsOf 584 initially HIV-negative FSW-IDUs, retention was ≥90%. After 12 months, HIV/STI incidence decreased >50% in the interactive vs. didactic sex intervention (Tijuana:AdjRR:0.38,95% CI:0.16–0.89; Juarez: AdjRR:0.44,95% CI:0.19–0.99). In Juarez, women receiving interactive vs. didactic injection risk interventions decreased receptive needle-sharing by 85% vs. 71%, respectively (p = 0.04); in Tijuana, receptive needle sharing declined by 95%, but was similar in active versus didactic groups. Tijuana women reported significant increases in access to syringes and condoms, but Juarez women did not.InterpretationAfter 12 months in both cities, the interactive sexual risk intervention significantly reduced HIV/STI incidence. Expanding free access to sterile syringes coupled with brief, didactic education on safer injection was necessary and sufficient for achieving robust, sustained injection risk reductions in Tijuana. In the absence of expanding syringe access in Juarez, the injection risk intervention achieved significant, albeit more modest reductions, suggesting that community-level interventions incorporating harm reduction are more powerful than individual-level interventions.Trial Registrationclinicaltrials.gov NCT00840658

Objectives To determine sociodemographic and behavioral correlates of HIV infection among male clients of FSWs in Tijuana. Methods 400 men aged 18 or older who had paid or traded for sex with a FSW in Tijuana during the past 4 months were recruited in Tijuana’s “zone of tolerance,” where prostitution is practiced openly under a municipal permit system. Efforts were made to balance the sample between residents of the U.S. (San Diego County) and of Mexico (Tijuana). Participants underwent interviews and testing for HIV, syphilis, gonorrhea, and Chlamydia. Logistic regression identified correlates of HIV infection. Results Mean age was 36.6. One quarter had injected drugs within the previous 4 months. Lifetime use of heroin, cocaine and methamphetamine was 36%, 50% and 64%, respectively. Men had frequented FSWs for an average of 11 years, visiting FSWs an average of 26 times last year. In the past four months, one half reported having unprotected sex with an FSW; 46% reported frequently being high when having sex with an FSW. Prevalence of HIV, syphilis, gonorrhea, and Chlamydia was 4%, 2%, 2.5% and 7.5%; 14.2% were positive for at least one infection. Factors independently associated with HIV infection were living in Mexico, ever using methamphetamine, living alone, and testing positive for syphilis. Conclusions Male clients of FSWs in Tijuana had a high sex and drug risk profile. While STI prevalence was lower than among FSWs, HIV prevalence was comparable, suggesting the need for interventions among clients to prevent spread of HIV and STIs.