P49 - To Chill or Not to Chill? Optimizing Storage Duration and Temperature for Culex quinquefasciatus Egg Raft Shipping

West Nile Virus is the leading cause of arboviral disease in the continental United States and is vectored by Culex mosquitoes. The reliable shipping of Culex egg rafts is essential for collaborative research related to the control of West Nile Virus. Unlike Aedes spp. eggs, the methods for shipping egg rafts are not standardized and can be unreliable, due to their inability to survive desiccation.

The effects of storage duration and temperature on Culex quinquefasciatus egg rafts prior to shipping were evaluated to determine impact on egg viability. Individual egg rafts were divided, with half stored at room temperature (20°C) or under refrigeration (0-4°C) for 12, 24, or 48 hours.  The remaining half was immediately hatched as a control. Hatch rate and the number of larvae that reached second instar were recorded. For every hour egg rafts were stored under refrigeration, larvae survivability decreased by 10%. To maximize survivability, egg rafts should not be stored under refrigeration for longer than 12 hours prior to shipment.

The optimization of Culex egg rafts storage prior to shipping can help provide standardization for storage conditions. Standardization of shipping can lead to more successful Culex egg raft shipments and ultimately increase collaborative research with field caught and laboratory reared Culex quinquefasciatus.