Screening for Zika virus in US armed services blood program donors: An opportunity to compare emerging infectious disease risk between the general US population and military donors

Background: The U.S. Department of Defense (DoD) collects blood from volunteer DoD donors in U.S. Food and Drug Administration (FDA)-regulated centers, and from emergency donor panels in overseas operations. Emerging infectious diseases could reduce DoD access to blood products. In August 2016, FDA determined that Zika virus was transfusion-transmitted and advised that donated blood should be screened for Zika utilizing one of two investigational new drug (IND) applications. The Armed Services Blood Program (ASBP) tested blood using its own protocol concurrently with the IND study sponsored by Roche Molecular Systems, Inc., titled “A Prospective Study to Evaluate the Specificity of the cobas Zika test for use on the cobas 6800/8800 System for Screening of Blood Donations for the Presence of Zika virus RNA.”. Study Design and Methods: This prospective clinical trial (September 2016–August 2017) evaluated the specificity of the cobas Zika 6800/8800 System. Consenting volunteers were screened for Zika by participating reference labs. Participants with positive screens were offered a follow-up study using alternative PCR and serology assays. Results: 92,618 DoD donors enrolled; four tested positive on screening (0.0043%; CI 0.001176896%, 0.01105894%). Three enrolled in follow-up testing and none were positive. These results were comparable to all U.S. donors: 3,858,114 enrolled (excluding Puerto Rico) with 459 positive screens (0.0119%; CI 0.01083582%, 0.01303962%). Conclusion: The study demonstrated the effectiveness of the cobas Zika test. DoD donors, who are included in emergency donor panels during military operations, were at no higher risk for Zika than the overall U.S. donor population.