OBJECTIVE To detect antibodies to six potentially blood-borne infections in blood donors at a social security institute in Querétaro, Mexico. METHODS A cross-sectional, retrospective, descriptive study was performed using data from the blood bank records of the General Regional Hospital No. 1, Mexican Social Security Institute (IMSS). From the 6 929 registered donors, those with any antibody to brucellosis, Chagas' disease, hepatitis B, hepatitis C, syphilis, and HIV were identified. For the cases presenting any of these infections, the following demographics were analyzed: age, gender, marital status, education, home address, and number of donations made. To estimate overall prevalence, the number of donors with any of the antibodies was divided by the total donors, and then by each of the various infections. RESULTS Of the 6 929 donors, 144 were detected with some type of circulating antibody of the six potentially blood-borne infections, with a total prevalence of 2.07% (0-4.4). The prevalence of blood donors with antibodies for hepatitis C was 0.721% (95%CI: 0.522-0.920) and Chagas' disease, 0.649% (95%CI: 0.460-0.838). CONCLUSIONS Identifying the prevalence of blood donors with antibodies for any of these six, potentially blood-borne infections, allows the blood bank at the General Regional Hospital No. 1 to establish its own epidemiologic profiling. Chagas' disease proved to be emergent, calling for urgent control efforts.