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Background In Brazil nationally representative donor data are limited on HIV prevalence, incidence and residual transfusion risk. The objective of this study was to analyze HIV data obtained over 24 months by the REDS-II program in Brazil. Methods Donations reactive to 3rd and 4th generation immunoassays (IAs) were further confirmed by a less-sensitive (LS) IA algorithm and Western blot (WB). Incidence was calculated for first-time (FT) donors using the LS-EIA results and for repeat donors with a model developed to include all donors with a previous negative donation. Residual risk was projected by multiplying composite FT/repeat donor incidence rates by HIV marker-negative infectious window periods. Results HIV prevalence among FT donors was 92.2/105 donations. FT, repeat donor and composite incidence were 38.5 (95%CI: 25.6–51.4), 22.5 (95%CI: 17.6–28.0) and 27.5 (95%CI: 22.0–33.0) per 100,000 person-years, respectively. Male and community donors had higher prevalence and incidence rates than female and replacement donors. Estimated residual risk of HIV transfusion-transmission was 11.3 per 106 donations (95%CI: 8.4–14.2), which could be reduced to 4.2 per 106 donations (95%CI: 3.2–5.2) by use of individual donation nucleic acid testing (NAT). Conclusion Incidence and residual transfusion risk of HIV infection are relatively high in Brazil. Implementation of NAT testing will not be sufficient to decrease transmission rates to levels seen in the US or Europe, therefore other measures focused on decreasing donations by at-risk individuals are also necessary.

BACKGROUND-The profile of blood donors changed dramatically in Brazil over the past 20 years, from remunerated to non-remunerated and then from replacement to community donors. Donor demographic data from three major blood centers establish current donation profiles in Brazil, serving as baseline for future analyses and tracking longitudinal changes in donor characteristics.