HIGH FREQUENCY OF HTLV-III ANTIBODIES AMONG HETEROSEXUAL INTRAVENOUS DRUG ABUSERS IN THE AUSTRIAN TYROL

34 intravenous drug abuse prisoners (5 females 2 of whom were prostitutes and 29 heterosexual males; aged 20-34) have been tested for antibodies to human T-lymphotropic virus type III (HTLV-III) both in Innsbruck (by enzyme-linked immunosorbent assay (ELISA) and immunoperoxidase straining. No one had had a recent infection at the time of the study. All these drug abusers had used intravenous opioids for 1-12 years and 18 had also taken cocaine in the 2-12 years before the study. However they had been free of drugs since their imprisonment 1 week to 18 months ealier. Immunological studies were done by fluorescence-activated cell sorting with antibodies Leu 3a Leu 2a. Neopterin a marker of the activation status of the cellular immune system was measured in urine and serum by high performance liquid chromatography and radioimmunoassay respectively. Raised neopterin levels have been found in AIDS patients and in risk groups for AIDS. Serum antibodies to HTLV-III were found in 15 (44%) of the drug addicts 14 seropositive individuals being heterosexual males and 1 a female prostitute. 15/29 (52%) had reversed helper-suppressor lymphocyte ratios. Neopterin levels were raised in 16/33 (48%) urine and 15/34 (44%) serum samples. The HTLV-III seropositive and seronegative groups were similar in respect of previous hepatitis infections hepatitis A and B virus antigen-antibody status duration and type of drug abuse and detoxification time. HTLV-III seropositive drug abusers were more likely to have raised neopterin levels and reversed T-helper suppressor ratios (0.9 or less). The significance of the raised neopterin levels in 4 subjects without HTLV-III antibodies is not clear. A prospective study is needed to show whether HTLV-III antibodies develop primarily among individuals with increased neopterin levels or independently of neopterin levels. The frequency of HTLV-III antibodies in drug abusers in the Austrian Tyrol is high compared with figures from the United States Britain and West Germany especially since the drug abusers we studied although in prison at the time do not live in an area of high risk for AIDS. The high frequency of HTLV-III in drug abusers has implications for the spread of the virus into the community at large since the heterosexual group especially after rehabilitation will not be so limited in their social contacts as homosexuals are. Futhermore some drug addicts are non-registered prostitutes. (full text)