SEX AS A RISK FACTOR FOR HTLV-I SPREAD AMONG INTRAVENOUS DRUG ABUSERS

289 intravenous drug abusers attending public assistance centers in Rome were studied to evaluate the correlation between HTLV-1 and specific behaviors such as needle sharing and sexual promiscuity. HTLV-1 is a virus which is widespread in certain areas and endemic in southeastern Italy. High rates of seropositivity have been found in intravenous drug addicts and is probably transmitted by routes similar to those for HIV the AIDS virus. HTLV-1 seropositivity was significantly more common among anti-HIV-positive individuals (p<0.001) suggesting similar ways of transmission. Needle sharing was more frequent in seropositives than in seronegatives but the difference was not significant. A closer association was found between HTLV-1 seropositivity and sexual promiscuity. Logistic regression analysis confirmed an association between sexual promiscuity and seropositivity for HTLV-1 and revealed an even stronger association when interaction between sexual promiscuity and needle sharing was also taken into account. These findings emphasize the importance of sexual contact besides needle sharing in determining HTLV-1 spread among intravenous drug abusers.