[Epidemiological characteristics of new HIV infections compared with AIDS cases. The HIV/AIDS epidemic in the Basque Country]. / Características epidemiológicas de las nuevas infecciones causadas por el VIH comparadas con los casos de sida. La epidemia de VIH/sida en el País Vasco.

OBJECTIVE: To describe the epidemiological characteristics of new cases of HIV infection diagnosed from 1997-2001 and compare them with AIDS cases (1991-2001). METHODS: Data were retrospectively collected on new cases of HIV infection detected in the Basque Country (1997-2001) and were compared with AIDS cases (1991-2001). RESULTS: A total of 912 new cases of HIV infection were diagnosed. In 299 of the new cases (32.8%), HIV and AIDS were diagnosed simultaneously. The most common mechanism of transmission was heterosexual transmission, followed by intravenous and homo/bisexual transmission. Significant epidemiological differences (p < 0.001) were found with regard to AIDS cases. CONCLUSIONS: Sexual transmission has replaced intravenous drug use as the most common mechanism of HIV transmission. A large percentage of patients were simultaneously diagnosed with HIV and AIDS, indicating the need for new prevention strategies.