Development and application of an antigen capture ELISA assay for diagnosis of Japanese encephalitis virus in swine, human and mosquito

BACKGROUND: Japanese encephalitis (JE) is a serious zoonosis caused by the Japanese encephalitis virus (JEV) which is a mosquito-borne pathogen of the family Flavivirus. However, the application of several developed laboratory methods for the detection of JEV antigens or antibodies are limited by their requirements of laboratory operations, skilled technicians and special facilities. RESULTS: To develop a method for detecting JEV antigen in swine, human, mosquito and other clinical specimens specifically, conveniently and effectively, an antigen capture enzyme-linked immunosorbent assay (ELISA) was established in this study. Sensitivity, specificity, repeatability and stability of the developed method were evaluated, and 60 clinical samples were tested in this study. The results demonstrated that the antigen capture ELISA was capable in detecting JEV antigen with high sensitivity and specificity compared with conventional methods. 14 samples showed the positive result with coincidence rate of 70%, and 46 displayed negative result with coincidence rate of 100% as compared to that of reverse transcription-polymerase chain reaction (RT-PCR). CONCLUSIONS: The developed ELISA assay provides a convenient and specific method for the large-scale determination of JEV antigen in infected swine, human and mosquito samples with high sensitivity and specificity.