** AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** THE EMERGENCE OF LETHAL VIRUSES HAVE NEGATIVELY IMPACTED THE CULTURE OF WHITE STURGEON FOR FOOD OR RESTORATION EFFORTS IN THE PACIFIC NORTHWEST (PNW) OF NORTH AMERICA FOR DECADES. AN IRIDO-LIKE VIRUS IS THE MOST SIGNIFICANT PATHOGEN OF JUVENILE WHITE STURGEON (WHITE STURGEON IRIDOVIRUS; WSIV) RESULTING IN UP TO 95% MORTALITY UNDER INTENSIVE CULTURE. WSIV HAS ALSO BEEN DETECTED IN WILD WHITE STURGEON FROM THE LOWER COLUMBIA RIVER IN OREGON AND WASHINGTON, THE SNAKE RIVER IN SOUTHERN IDAHO, AND THE KOOTENAI RIVER IN NORTHERN IDAHO. DESPITE THE THREAT THIS VIRUS POSES, NO SURVEILLANCE PROGRAMS ARE IN PLACE DUE TO THE UNAVAILABILITY OF MOLECULAR DIAGNOSTIC ASSAYS. DEVELOPMENT OF MOLECULAR VIRAL DIAGNOSTIC ASSAYS HAS BEEN HAMPERED BY THE MINIMAL GENOMIC SEQUENCE DATA AVAILABLE FOR WSIV. TO FILL THIS INDUSTRY NEED, WE PROPOSE THE FOLLOWING RESEARCH OBJECTIVES TO: 1) SEQUENCE, ASSEMBLE, AND ANNOTATE THE GENOMES OF WSIV ISOLATES; 2) PERFORM PHYLOGENETIC ANALYSES TO UPDATE THE TAXONOMY OF WSIV; 3) DEVELOP, OPTIMIZE, AND VALIDATE THE ANALYTIC PERFORMANCE OF A QUANTITATIVE PCR (QPCR) AND RAPID CRISPR DIAGNOSTIC ASSAY FOR THE DETECTION OF WSIV; AND 4) PERFORM EXPERIMENTAL WSIV CHALLENGES TO GENERATE KNOWN POSITIVE AND NEGATIVE SAMPLES TO DETERMINE THE DIAGNOSTIC PERFORMANCE OF THE WSIV QPCR AND CRISPR ASSAYS COMPARED TO CONVENTIONAL PCR ASSAYS (GOLD STANDARD). THIS TECHNOLOGICAL LEAP FORWARD IN SCIENCE WITH THE DEVELOPMENT OF BOTH HIGH-SENSITIVITY QPCR AND RAPID ON-SITE CRISPR VIRAL DIAGNOSTICS WILL ENSURE U.S. FARMERS CAN SUSTAIN THE ICONIC WHITE STURGEON FISHERY THROUGHOUT THE PNW WHILE PROTECTING DOMESTIC/INTERNATIONAL MARKETS OF FILLETS AND CAVIAR.