Zika Virus and Related Arbovirus Infections in Deferred Blood Donors (ZVADD)

Background: Zika virus is mostly passed on by the bite of an infected mosquito. It usually causes mild illness. But in pregnant women it can cause serious birth defects to the baby. The virus can also spread by blood transfusion and sexual intercourse. This is why the U.S. Food \& Drug Administration (FDA) recommended that people should not give blood if possibly exposed to Zika virus. Dengue virus and chikungunya virus are passed by the same mosquitoes as Zika virus. These can cause severe reactions if passed through transfused blood. Donated blood is usually not tested for these three viruses. Researchers want to count the infections in people who have been exposed because of travel or sexual exposure. They want to learn the risk these viruses might pose to the U.S. blood supply. They also want to study the natural history of these viruses by following infected people over time. Objective: To study the risk of Zika, dengue, and chikungunya viruses to the U.S. blood supply. Eligibility: Adults age 18 or older who were turned down for donating blood because of possible exposure to certain viruses. Design: Participants will have blood and urine tests. They will answer questions about their travel. They will be called in about a week with virus test results. Participants with negative results do not have any more study visits. Participants with positive results will be asked to stay in the study for 6 months. They will have weekly clinic visits and tests until results are negative for 2 straight weeks. Once test results are negative, they will have monthly visits. Visits will include physical exams, blood and urine samples, and optional semen samples from men. Most people will have 3-4 weekly visits and 5 monthly visits.