Risk behaviours for HIV infection among injecting drug users attending a drug dependency clinic.

To study a range of possible risk factors for HIV among injecting drug user patients attending a clinic in London were interviewed from November 1986 to November 1987. Serum samples were tested for viral markers. Of 116 patients, 101 had shared injecting equipment, 75 on the first occasion of injecting and 76 during the past year. Seventy said that sharing was because equipment was not available. In the past year 102 had been sexually active, a third having two to 20 partners; a quarter of the women had exchanged sexual intercourse for money. The four patients who were positive for antibody to HIV antigen had shared equipment or had intercourse with drug users from areas with a high prevalence of HIV. Eleven patients had injected drugs while in prison. Despite a low prevalence of HIV infection this infection remains a threat to drug users in London; strenuous efforts are still needed to prevent its further transmission.