The results of a cross sectional sample of unpaid voluntary blood donors from 6 out of 8 blood banks in Goiania Brazil in 1989 are reported. The population of 6184 interviewed constitute 50% of all blood donors in the 6 banks during a mean of 106 working days/blood bank. The purpose of the study was to monitor trends in HIV infection. 219 cases of AIDS have been reported up to 1990 in Central Brazil and incidence is estimated as 24.7/1 million inhabitants. This figure is 7 times lower than cases estimated for the State of Sao Paulo. Screening conducted on 58111 blood donations between 1985-87 has produced a seroprevalence rate of .07% for HIV infection. Blood analysis was performed with ELISA (Hoechst). The 1989 results showed a seroprevalence rate of .26% or .20% for 1st time donors and .28% for regular donors. Although regular donors were higher it was not statistically significant. 13% of 1st time donors were women and 3% of regular donors and none tested positive. Male seroprevalence was .27% or .23% for 1st time donors and .29% for regular donors. Between 1985-87 and 1989 there has been a 4-fold increase in HIV prevalence. However the ELISA test has been known to have a low positive predictive value in areas o flow prevalence and confirmation is required.