The objectives of the Recipient Epidemiology and Donor Evaluation Study-IV-Pediatric (REDS-IV-P) program is to evaluate and improve the safety and availability of the blood supply as well as the safety and effectiveness of transfusion therapies with attention to not only adults but also neonates and children who need transfusion. REDS-IV-P is a seven-year multicenter program in the US and in Brazil charged with conducting epidemiologic and laboratory studies in blood donors and transfusion recipients. The REDS-IV-P Program is comprised of 4 domestic hubs and a Brazil transfusion program involving U.S. investigators and investigators at international blood centers. The domestic Hubs and the Brazil international programs are supported by one data coordinating center (DCC) and one center for transfusion laboratory studies (CTLS). The REDS-IV-P Brazil Transfusion Safety Research Program is a 7-year program consisting of three phases, each with the following specific endpoints: 1) Phase 1 (Years 1-2): Development of the Phase 2 multi-site research portfolio; conduct of a pilot study to establish the donor and donation database; development and implementation of the next phase of the sickle cell disease (SCD) cohort study; and, as appropriate, conduct of Phase 1 research studies that address blood safety and transfusion research priorities for patients with SCD as well as in non-SCD settings, and inform the nature of the Phase 2 research portfolio; 2) Phase 2 (Years 3-5): Conduct of the Phase 2 multi-site research portfolio including database(s) compilation, longitudinal follow -up of the Brazil SCD cohort study, and conduct of Phase 2 research studies that address key blood safety and transfusion research priorities; and 3) Phase 3 (Years 6-7): Conduct of Phase 3 research studies in SCD and non-SCD settings to address new or emerging research questions, as appropriate; dissemination of research findings through presentations and publications; and provision of resources such as sharable datasets to the external research community. This contract is for the base period of the Brazil Program for phase 2.