The objective of this study was to determine the prevalence of reactive infectious markers at the Centro Hemodador Regional de Loreto from november 2023 to december 2024. A quantitative, descriptive, and retrospective approach was applied. Data from 7,767 donors were analyzed, who underwent screening with infectious markers using the chemiluminescence technique, allowing for a detailed analysis of the prevalence and distribution of these agents in the donor population. Seven mandatory markers in blood banks were evaluated, and for the purposes of the study, sociodemographic variables such as age, sex, marital status, origin, ABO group, and Rh factor were categorized. The overall prevalence of reactive markers was 8.1%. The most frequent marker was anti-HBcAb (4.49%), followed by anti-syphilis (1.47%), anti-HCV (0.61%), anti HTLV-I/II (0.57%), anti-HIV 1-2 (0.37%), HBsAg (0.22%), and anti...