The epidemiology of HIV among Mexican migrants and recent immigrants in California and Mexico.

For Mexican migrants and recent immigrants, the impact of migration from Mexico to California has the potential to lead to an increased risk for HIV infection. Until recently, the prevalence of HIV in Mexico and among Mexican migrants in California appeared to be stable and relatively low. Recent studies have raised new concerns, however, that the HIV epidemic may expand more aggressively among this population in the coming years. Unfortunately, the insufficient amount of data available within recent years makes it difficult to fully assess the potential for rapid spread of the HIV epidemic among this population. Consequently, there is a critical need for an ongoing binational surveillance system to assess prevalence and trends in HIV/STD/TB disease and related risk behaviors among this population both in Calfornia and within this population's states of origin in Mexico. This enhanced epidemiologic surveillance system should provide improved data on the subpopulations at the highest risk for HIV/STD/TB, such as men who have sex with men, and should provide the opportunity to evaluate the impact of migration on the transmission dynamics, risk behaviors, and determinants of behavior on each side of the border. It is essential that this potential threat be assessed and that intervention programs are developed and implemented to combat this possible escalation in the HIV epidemic.