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

University of California San Diego, School of Medicine, San Diego, California, USA.
The International Journal of Tuberculosis and Lung Disease (Impact Factor: 2.32). 06/2009; 13(5):626-32.
Source: PubMed


We studied prevalence and correlates of latent tuberculosis infection (LTBI) among injection drug users (IDUs) in Tijuana, Mexico, where tuberculosis (TB) is endemic.
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.
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.
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.

Download full-text


Available from: Steffanie A Strathdee
  • Source
    • "Whether a country is struggling to eliminate TB, and needs to invest additional resources to effectively provide those who are hardest to reach (see section: vulnerable populations), screening selected high-risk groups may be a key part of the response to tackle TB. In this regard, some studies have used IGRAS in Mexican population, but those studies have been focused in some risk groups such as injection drug users [76], migrant agricultural workers [77], PTB contacts [78,79], dairy farm and abattoir workers [80], and HIV-infected people [81,82]. Controversial results have emerged when comparing TST and IGRAS [83]. "

    Full-text · Chapter · Jun 2015
  • Source
    • "As noted above, nearly all PWID in Tijuana (95%) are HCV-positive [38,39], while PWID in San Diego were found to have comparatively low HCV prevalence (27%) [64]. Similarly, in contrast to the high prevalence of LTBI among PWID in Tijuana [65], less than 15% of HIV-positive PWID tested in a San Diego HIV clinic were found to have LTBI [40,41]. The disparities in disease prevalence between Tijuana and San Diego raised concerns that PWID travelling from the United States to Mexico to buy or use drugs could face increased risk of acquiring these diseases through social, sexual, or drug use interactions [64]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: 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. 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 factor 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. 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. 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.
    Full-text · Article · Feb 2014 · Harm Reduction Journal
  • Source
    • "These sampling weights allowed us to adjust for participants' different social network sizes (i.e., different numbers of potential recruits) and homophily within recruitment dyads (i.e., the tendency of recruiters to recruit others similar to themselves), thereby minimizing the bias introduced by the sampling method. Although there is currently no consensus on appropriate regression modeling of RDS data (Johnston, Malekinejad, Kendall, Iuppa, & Rutherford, 2008), sampling weights are an increasingly accepted approach (Garfein et al., 2009; Jenness et al., 2011; Townsend et al., 2010; Wayal et al., 2011). To maximize statistical power, we imputed any missing data. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Abstract Immigrant Sexual minority Latino men-who may or may not self-identify as gay-constitute a minority within a minority. Often labeled "hidden" and "hard-to-reach," and marginalized along multiple dimensions, it is a sub-group about whom little is known. Informed by a Social Ecological Framework, we sought to describe key social variables for 190 such men in rural North Carolina and to test associations with three sexual outcomes: consistent condom use, number of sex partners, and sexual compulsivity. Participants reported limited English-language use, predominantly Latino close friends, middle levels of social support despite numerous social ties, and frequent experiences of discrimination. There were unique sets of correlates for each sexual outcome. Findings may inform health promotion interventions and guide future research.
    Full-text · Article · Dec 2013 · Journal of Homosexuality
Show more