Inter-laboratory study to validate new rapid screening methods for Kudoa septempunctata

Abstract

Kudoa septempunctata is the causative agent of a food-borne disease associated with the ingestion of raw olive flounder. As the current qRT-PCR method for its detection is time-consuming, a rapid and simple method is required. Recently, a new real-time loop-mediated isothermal amplification (LAMP) method and an immunochromatography method, whose sensitivities are intended to be compatible with that designated in the official analytical method (105 spores/g olive flounder), have been developed. To validate these new methods, we performed an inter-laboratory study across seven laboratories. Both methods could not detect less than 104 spores/g; however, these methods were able to detect more than 105 spores/g in olive flounder samples. These results demonstrated that the sensitivities of these methods were compatible with the designated level in the official analytical method. We concluded that these new methods were acceptable as the screening methods for K. septempunctata.