HIV and HCV infection among drug users in Japan

To assess seroprevalence of human immunodeficiency virus (HIV), hepatitis C virus, injecting drug use, unsafe sexual behaviours, self-mutilation and tattoos in patients attending a drug and alcohol treatment centre in Japan.

Cross-sectional survey.

The work was carried out at the National Sanitarium of Shimousa, Chiba, Japan, a 32-bed inpatient centre specializing in drug and alcohol treatment.

Laboratory analyses for HIV antibody, hepatitis C antibody, hepatitis B antigen and antibody; questionnaires for history of sexual activities, needle and syringe use; physical examination with assessment of self-amputated finger joints, tattoos, scars from lacerations and cigarette burns.

No patients tested positive for anti-HIV. The seroprevalence of anti-HCV positives was 53.8% of methamphetamine-dependent patients, 18.4% of solvent-dependent patients and 5.6% of alcohol-dependent patients. Past needle sharing was reported by 82.1% of methamphetamine-dependent patients, 18.4% of solvent-dependent patients and 5.6% of alcohol-dependent patients. A history of syringe sharing was reported by 87.2% of methamphetamine-dependent patients. More than two-thirds of all patients reported contact with commercial sex workers. Casual sexual contacts were more common among solvent and methamphetamine-dependent patients than those dependent on alcohol. Tattoos and cigarette burns were more common among methamphetamine and solvent-dependent patients than among alcohol-dependent patients. Among the methamphetamine-dependent patients, 20.5% reported self-amputated finger joints compared with none in the other patient groups.

HCV prevalence is a significant problem among methamphetamine users in Japan, probably because of a high rate of needle and/or syringe sharing. Although HIV infection is currently negligible, the very high rate of needle and syringe sharing could give rise to a significant increase in the HIV rate among drug users in the future.