1. Borderline: Cross-border Mobility and its Link to Transmission of HIV, Syphilis and TB in the Mexico-US Border Region Steffanie A. Strathdee, Ph.D. Associate Dean of Global Health Sciences, Harold Simon Professor; Chief, Division of Global Public Health, Department of Medicine, University of California, San Diego sstrathdee@ucsd.edu

2. Overview Unique features about the context of HIV risks along the Mexico/U.S. border Recent border studies –HIV –Syphilis –TB Influencing policy

3. U.S.MEXICO

4. U.S.

5. What makes the Mexico-US border region different? Volume of cross-border traffic ~60 million crossings per year Major drug trafficking route Sex work is quasi-legal Main corridor for migration fueled by huge economic disparities >>Confluence of risk factors for infectious diseases (e.g. HIV, STIs, TB)

6. Major U.S. Drug Trafficking Routes Source: National Drug Intelligence Center, National Drug Threat Assessment 2006 Tijuana Major US Drug Trafficking Routes Cd. Juarez

7. Tijuana has one of the fastest growing populations of injection drug users (IDUs) in Mexico, with ~21,000 drug users, and ~10,000 IDUs

8. Most frequent drug injection sites in Tijuana (n=995)

9. 2/3 rds born Outside of Baja California Place of Birth among Tijuana’s Injection Drug Users Number of subjects

10. HIV and Migration: What is the link? Family separation, changes in cultural environment, homelessness, poverty, social isolation, greater sense of anonymity (Deren, 2003; Lagarde, 2003; Organista et al, 2004; Parrado, 2004) Mobility can increase the chance of encountering HIV- positive persons (Kottiri et al, 2002) Mobile persons can act as bridge populations between groups that normally wouldn’t interact (Paschane, 2000) Mobility can change sexual networks in the sending or receiving community (Aral, 2007)

11. San Diego Tribune, Reuters, CNN, March 1, 2006

12. ADAPTED FROM: Report on the Global AIDS Epidemic, UNAIDS, 2008 Tijuana

13. Reasons for moving to Tijuana, by gender

14. Factors Independently Associated with HIV infection by Gender Variable Adjusted Odds Ratio (Females) Adjusted Odds Ratio (Males) Age 0.84-- # of arrests for track marks (per 5 arrests) --1.1 Syphilis 4.86.2 # of different people usually injects with* (per 5 people) --1.3 Number of years lived in Tijuana (per 10 year increase) 1.9-- Deportation--4.0 All p<0.05

15. Explanation #1: Is Deportation a marker for a high risk subgroup of male IDUs who acquired HIV in the US? Courtesy of La Frontera, 2008

16. Explanation #2: Is Deportation a Risk Factor for HIV Acquisition? All photos shared with permission

17. Impact of deportation on families

18. HIV Prevalence and Incidence among IDUs in Tijuana: 2006-2008 Prevalence Male IDU HIV Prevalence

19. Sex Work in Mexico Quasi legal in Mexico –Zone of tolerance (zona roja) –Work permit Up to 9000 FSWs in Tijuana, ~4000 in Ciudad Juarez Many women/girls from S. Mexico/Central America ‘Sex tourism’ is common

20. Sex work in the Mexico-US Border Region 70% of FSWs in Tijuana and Cd. Juarez are migrants Migrant FSWs have: – Lower HIV and STI prevalence –Less drug use –More condom use Over time, protective factors associated with being a migrant appear to erode Ojeda et al, Sex Transm Infect 2009

21. Factors associated with HIV infection in FSWs in Tijuana and Ciudad Juarez (n=924) Patterson et al, J Inf Dis (2008) * HIV prevalence: 6% * Consistent with active infection

22. Male Clients of FSWs in Tijuana and Ciudad Juarez 70% of FSWs have U.S. clients FSWs with U.S. clients more likely to have: –Syphilis titers ≥ 1:8 –Injected drugs –High client volumes – Been paid more for unprotected sex Strathdee et al, Sex Trans Dis 2008

23. Prevalence of HIV testing and HIV/STIs among Mexican (N=200) and U.S. clients (N=200) of Tijuana FSWs Prevalence Patterson et al, AIDS 2009

24. Factors Independently Associated with HIV Infection among Male Clients of FSWs in Tijuana, Mexico (N=400) Variable Adjusted Odds Ratio 95% Confidence Interval Resides in Mexico (vs. United States) 2.260.91–5.58 Lives alone2.881.23–6.71 Ever used methamphetamine4.341.31–14.36 Tested positive for syphilis9.362.41–36.42 Patterson et al, AIDS 2009

25. HIV TB Syphilis

26. CA AZ NM TX SON CHI COH TAM NL B.C. 3.8 7.4 United States National syphilis incidence: 4.5 (2008) Mexico National Syphilis Incidence: 1.2 (2007) Syphilis Incidence on the U.S.-Mexico Border (Per 100,000) Sources: CONASIDA, US Centers for Disease Control, SD County Health Dept San Diego (increased from 3.8 to 11.8 from 2003 to 2007) 5.7

27. California – Primary and Secondary Syphilis Rates by County, 2008 Source: California Department of Public Health, STD Control Branch Mexico

28. Prevalence of HIV and lifetime syphilis infection among high risk groups in Tijuana and Cd. Juarez (2004-2009)

29. Proportion of Lifetime Syphilis Infections with current titers > 1:8* by Risk Group in Tijuana and Cd. Juarez *Consistent with active infection

30. ADAPTED FROM: Report on the Global AIDS Epidemic, UNAIDS, 2008 Tijuana

31. HIV TB Syphilis

32. TB - The forgotten epidemic

33. CA AZ NM TX SON CHI COH TAM NL B.C. 25.418.7 11.7 31.1 57.3 21.9 7.5 4.82.6 6.3 United States National TB Incidence: 4.4 Mexico National TB Incidence: 15.7 TB Incidence on the U.S.-Mexico Border Source: CDC, USA,2007 & DGE Mexico, 2004. Incidence per 100,000 population San Diego (9.0)

34. HIV and TB Co-infection: What’s the link? Of ~42 million people with HIV worldwide, one third also have TB. Among HIV+ people, risk of progressing from latent to active TB is 10% per year.

35. Trends in HIV-TB Co-infection in San Diego by Ethnicity (1993-2007)

36. Factors independently associated with HIV-TB co-infection in San Diego (1999-2007)* CharacteristicAdjusted * Odds Ratio 95% Confidence Interval Age in years** 30-39 years3.232.11 - 4.95 Male sex2.861.97 - 4.14 Hispanic ethnicity3.902.79 - 5.45 Ever injected drugs2.301.19 – 4.43 *Odds ratios are adjusted for all other variables in the table. **reference group: 20-29 years Rodwell et al, AJPH 2010

37. Prevalence of Latent TB Infection (LTBI)* among High Risk Populations in Tijuana, Mexico Prevalence IDUs (N=232 ) Non-IDUs (N=311) FSWs (N=115) Homeless (N=280) LTBI incidence among IDUs (N=503 ) *Tested through IGRA (Quantiferon Gold), Cellestis Inc; IDUs=injection drug users; FSWs= female sex workers. Garfein et al, Emerg Inf Dis (in press)

38. Factors associated with tuberculosis infection among high risk groups for HIV in Tijuana: 2007 CharacteristicAdjusted * Odds Ratio (95% Confidence Interval) Age in years1.03 per yr(1.01 – 1.05) Years lived in Tijuana1.02 per yr(1.01 – 1.04) Location of incarceration Never jailed1.00 Jailed in US only1.61(0.98 – 2.63) Jailed in Mexico, or BOTH US and Mexico 2.28(1.48 – 3.51) * Odds ratios are adjusted for all other variables in the table. Garfein et al, in press

39. Characteristics of Active TB Cases among IDUs in Tijuana (n=103/1060) Prevalence Previously Dx’ed with Active TB Active TB Dx’ed in US Received Anti-TB Meds TB tx Prematurely Stopped TB tx stopped due to deportation Deiss et al, AJPH 2009

40. Influencing Policy Donated a mobile vehicle for HIV prevention to our partner NGO which became the prototype for HIV service delivery across Mexico The Prevemovihl

42. 2010: Mexico to receive $76 M USD for HIV Prevention

43. Lessons Learned  The Mexico-U.S. border region is vulnerable to epidemics of HIV, syphilis and TB  Cross-border infectious disease transmission is bi-directional, and depends on factors such as:  Host  Agent  Environment (physical, social, economic, policy)

44. Implications  Mobility can confer either protection or risk shaping an individual’s risk of infection.  Immigration policies and health policies should not work at odds.  Discrimination and blame represent significant barriers to prevention and treatment of mobile populations in border regions.  Prevention and treatment for overlapping epidemics requires binational cooperation

45. Acknowledgements UCSD Center for AIDS Research, USAID National Institutes of Drug Abuse and Mental Health: K01 DA020364, R01 DA019829, RO1 MH065849 ; T32 DA023356 Staff from the PrevenCasa, A. C., Patronato Pro- COMUSIDA, UCSD, and Programa Companeros San Diego County Public Health Dept Most importantly, the participants who gave their time