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

Overview

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.

Zika virus (ZIKV) is an Aedes species mosquito-transmitted Flavivirus responsible for an ongoing epidemic in over twenty countries and territories in the Caribbean, and in North, Central and South America. A 20-fold increased risk of microcephaly has been reported in newborns of infected mothers in Brazil. Of nine identified pregnant travelers returning to the U.S. from areas with local ZIKV infection, five have experienced severe neonatal outcomes. ZIKV can be transmitted via blood transfusion and by sexual exposure to a ZIKV-infected man. In response, AABB (formerly the American Association of Blood Banks) made recommendations and the Food and Drug Administration (FDA) issued guidance for donor deferral based on 1) travel to locations with active ZIKV transmission; or for 2) sexual exposure to a man who has traveled to an area with active ZIKV transmission. Further, Aedes species mosquito vectors that transmit ZIKV also transmit dengue virus (DENV) and chikungunya virus (CHIKV). Areas with local ZIKV transmission also commonly have local DENV and CHIKV transmission. DENV and CHIKV are transmissible via blood transfusion and can result in severe outcomes in transfusion recipients. The primary aims of this study are to: 1) assess the prevalence of ZIKV, DENV and CHIKV infection (RNA-positives) among adults who attempted to donate blood but were deferred because of travel to places with local transmission of ZIKV, DENV and/or CHIKV (travel-deferred donors); 2) assess the prevalence of ZIKV infection (RNA-positives) among adults who attempted to donate blood who were deferred due to potential sexual exposure to ZIKV infection; 3) assess the prevalence of ZIKV, DENV and CHIKV infection (RNA-positives) among blood donors whose blood or platelets were collected and who called back to report any illness within 2 weeks of donation; and to 4) study the 24-week natural history of ZIKV, DENV and CHIKV infection among deferred adult donors who tested RNA-positive for any of these agents.