[Epidemiological vigilance for HIV/AIDS in Navarra].
Between 1985 and December 2000, 2,395 new cases of HIV infection were diagnosed in Navarra. The years showing the highest incidence were 1987 with 250 cases, and 1991 with 232 cases. Starting in 1993 a progressive decline can be observed, reaching 35 cases in the year 2000. In the same period, 1985-2000, 690 cases of AIDS were diagnosed amongst residents in Navarra. The cases of AIDS have undergone a similar decline in recent years, dropping from an average of about 60 cases per year in the first half of the 1990s to the 19 cases diagnosed in the year 2000. This tendency, which became evident from 1996 onwards in most countries of our area, can be attributed, at least in part, to the employment of more efficient treatments for HIV infection. In Navarra, the most frequent category of transmission between patients with AIDS was the use of drugs by intravenous means, a practice referred to by 71.2% of the persons diagnosed between 1985 and 2000. Twenty point seven per cent of the cases were attributed to sexual transmission (7% to homosexual practices and 14% to heterosexual practices) and 2.5% to other mechanisms (mother-child, hemoderivatives and transfusions). Although the cases of AIDS and HIV have declined in Navarra in recent years, the data from microbiology laboratories and the hospital services that treat persons with HIV infection indicate that a considerable number of new cases will continue to occur, which justifies the need to maintain the prevention programmes.