Objective: To compare the mechanisms of HIV/AIDS transmission reported by the epidemiological surveillance system information of the Chiapas State and those referred by HIV positive men interviewed in the Soconusco's region from the same state.
Methods: Databases containing information about the HIV/AIDS cases registered in the State of Chiapas and in the Soconusco's region were used. Additionally, 32 men previously detected as HIVpositive by the regional surveillance system answered a questionnaire about their sexual behavior and some socio-demographic characteristics. All participants provided a blood sample to identify antibodies against HIVusing two screening tests, ELISA and microagglutination, and one confirmatory test by Western blot.
Results: While the heterosexual transmission was predominant among HIV/AIDS cases reported by the epidemiological surveillance of Chiapas State and the Soconusco's (50.4% and 69. 40%, respectively), heterosexual transmission among the interviewed individuals was 36.7%.
Conclusions: Contrary to the proposal about a process of "heterosexualization" of HIV/AIDS epidemic in Chiapas State and particularly in the Soconusco's region, the present study suggest that homosexual and bisexual behavior continue to be the main routes of HIV transmission among men. These results also suggest the presence of a methodological limitation in the evaluation of sexual behavior among HIV-seropositive individuals in the region. A gender analysis about masculinity, would allow a better understanding ofthe social and cultural aspects of sexuality that are not evident when only the sexual practices are evaluated.