CD40LG and Japanese encephalitis: JE was confirmed by one or more of the following: a JE virus (JEV)-specific immunoglobulin M (IgM) antibody-capture enzyme-linked immunosorbent assay (MAC-ELISA) (Shanghai B & C Enterprise Development Co. Ltd, Shanghai, China) [10], reverse transcription semi-nested polymerase chain reaction (PCR), or virus isolation from serum or cerebrospinal fluid (CSF) obtained from patients with viral encephalitis who were admitted to local county hospitals.