HIV AND INFECTIONS OF SIMILAR TRANSMISSION PATTERNS IN A DRUG INJECTORS COMMUNITY OF SANTOS, BRAZIL

To study the prevalence of HIV and infections with related transmissio n patterns, we interviewed and obtained blood samples from 110 injecti ng drug users (IDUs), sampled by snowballing, from the city of Santos in the state of Sao Paulo, Brazil, where the estimated number of IDUs (10,000) comprises similar to 2% of the entire population. Seroprevale nce of HIV, hepatitis B and C. syphilis, and HTLV (1 and 2) was assess ed and compared with that in 197 blood donors from the same city, matc hed for age and gender. Risk behavior related to HIV was assessed by a standard questionnaire applied to the IDU sample. Univariate and mult ivariate analyses of the risk factors were performed. Seroprevalences found were 62% for HIV, 75% for HCV. 75% for HBV, 34% for syphilis, an d 25% for HTLV (1 and 2) among IDUs, which compare with 0.0%, 2%, 23%, 12%, and 1% for blood donors, respectively. The risk for parenterally transmitted infections in this IDU community was higher than that for sexually transmitted infections (odds ratio for syphilis, 3.57; hepat itis B. 10.0: and hepatitis C, 100). The results of the multivariate r isk analysis showed that daily rate of ID use >5 times/day (OR = 6.73) , not changing behavior to avoid AIDS (OR = 3.28), ID use >15 days/mon th (OR = 2.72), and ID use in the last 2 months (OR = 2.23) were the r isk behaviors significantly associated with HIV infection.