HIV-antibody testings among injecting drug users (IDUs) in the Stockholm area, 1984-91: information compiled from...

The available information about testings for HIV antibodies in injecting drug users (IDUs) carried out in Stockholm between 1984 and 1992 has been compiled. These testings were carried out mainly in special settings. The use of codes (the first 2 digits giving the age and the last 4 the 6 and checking figures in the individual's personal identity number) precluded exact identification of individuals; in most cases, however, complementary information made it possible to recognize patients at follow-up. The data indicated that 9,150 persons associated with current or previous drug addiction were tested. The first extensive testings were performed in 1985 and 1986. After this period, 4,500 persons were retested. 11% of the IDUs tested in 1984-85 were found to be HIV-antibody-positive. After 1988, 1% were estimated to seroconvert each year. While in the first phase the heroin users predominated among those infected, in later years the rates of newly diagnosed infections became similar for all types of IDUs. The age profiles of the IDUs tested were similar up to 1988, after which there was an indication that also younger persons had entered the scene. However, the infected IDUs discovered belonged mainly to the 'old' cohort born between 1950 and 1960.