P23 - Expanding Arboviral Surveillance Capacity in Canyon County, Idaho: From RAMP to Triplex RT-qPCR Monitoring of WNV, SLEV, and WEEV

Abstract: Over the past three years, the Canyon County Mosquito Abatement District (CCMAD) in southwestern Idaho has undertaken a sustained effort to enhance arboviral surveillance capabilities in Canyon County Idaho. Historically dependent on RAMP testing for West Nile Virus and RT-qPCR testing for St. Louis encephalitis virus (SLEV), Western equine encephalitis virus and confirmation of RAMP results through the Idaho Bureau of Laboratories (IBL), CCMAD initiated a transition to molecular virus surveillance beginning in 2023. Implementation of a triplex RT-qPCR workflow based on the Brault et al. (2015) protocol enabled in-house detection of WNV, SLEV), and WEEV with markedly improved sensitivity and reduced turnaround time. Initial validations revealed moderate variability compared to state lab results, prompting refinement of threshold settings and controls. Following these adjustments, result concordance exceeded 97% for WNV while SLEV and WEEV have not been detected. By 2024, CCMAD adopted the TaqMan™ Fast Virus 1-Step Multiplex Master Mix to improve assay consistency and introduced a Qiagen QIAvac vacuum manifold in 2025 to streamline RNA extraction using QIAamp Viral RNA kits. The QIAvac system reduced hands-on extraction time by over 40%, enabling greater throughput during peak mosquito activity. Procurement of a KingFisher Flex automated extraction platform has been completed and is projected to further reduce per-sample cost and labor beginning in 2026. Between 2023 and 2025, CCMAD’s internal testing capacity increased significantly, while the average per-test cost was cut in half. These improvements have strengthened CCMAD’s response capacity and reduced reliance on external laboratories, ensuring faster data turnaround for mosquito control operations. This progressive modernization of diagnostic infrastructure underscores the importance of local molecular capacity for sustained, cost-effective arboviral surveillance in mosquito abatement programs.