Esmeralda Iniguez, UC San Diego

Objective: Referred to as an "Epidemic Without Borders," the escalating HIV/AIDS epidemic in the U.S./Mexico border region is in urgent need of attention. Although the epidemic is currently concentrated there is potential for it to advance to a generalized level. Recent studies have estimated that 1 in 125 adults aged 15-49 in Tijuana is HIV-infected, with sub-groups most affected being men who have sex with men (MSM), injection drug user (IDUs), and female sex workers (FSWs). Given this urgent to targeted HIV prevention initiatives for these populations, we propose to 1) forecast the future of the HIV/AIDS epidemic among MSM, IDUs and FSWs within the next 10-30 years in Tijuana Mexico; 2) To determine the potential impact of various HIV prevention interventions on the future of the HIV epidemic in Tijuana, Mexico on MSM, IDUs and FSW, including i) increased uptake of voluntary testing and counseling for HIV (VCT); ii) increased condom use; iii) increased access to sterile syringes. To our knowledge there are no studies that have attempted to project the future of this epidemic for Tijuana, Mexico.

Methods: Based on available data from ongoing prospective studies of IDUs and FSWs in Tijuana, and publicly available estimates of HIV prevalence and behavior among MSM, statistical modeling techniques will be utilized to develop the best mathematical models predicting potential futures of the HIV epidemic separately for MSM, IDUs and FSWs. For each subpopulation, simulations will be generated to forecast the potential impact of expanded access to VCT, condoms and sterile syringes. A series of sensitivity analysis will also be conducted which will allow us to account for both high and low estimates for all modeling scenarios which will provide us with confidence intervals around our modeling estimates.

Conclusion: Studies of projection or forecasting are instrumental in helping prevent future epidemics. Knowledge of the potential number of HIV cases that can be averted by appropriate prevention efforts is an extremely important tool for public health professionals. Results of projecting the HIV epidemic in Tijuana could be used by public health professionals as well as governmental institutions for resource allocation, guiding policy and structuring prevention interventions on both sides of the border. Seeing as cross-border HIV transmission is an important public health concern for both sides of the border, interventions aimed at reducing transmission in Mexico will impact the HIV/AIDS epidemic in the U.S. Since the HIV epidemic in Tijuana is in its early stages, the results of our study will not only raise awareness, but also have the potential to avert future HIV/AIDS transmission. Additionally this project will help develop the career of a Latina HIV/AIDS epidemiologist, whose goals are to focus on HIV/AIDS related research with underserved populations.