[Detection of Japanese encephalitis virus in samples of JE patients by RT-PCR]

To set up and assess the feasibility of RT-PCR method for Japanese encephalitis virus (JEV) detection, and use this method to detect clinical specimens.

The sensitivity of this RT-PCR was measured by plaque formation test, and the specificity of primers was proved by detecting some other flaviviruses. This RT-PCR was also compared with PRHI.

JEV RNA could be detected successfully from viral culturing supernatants and from mouse brain infected by JEV. Its sensitivity of detecting JEV RNA from viral culturing supernatants was 64 PFU. A total of 38 specimens (of which 25 were serum specimens, 13 CSF specimens) from 16 clinically susceptible JE patients were examined by RT-PCR and RPHI Summing up the detection results of RT-PCR and RPHI, 14 patients among the 16 susceptible patients were affirmed as Japanese encephalitis patients. This RT-PCR is specific to JEV. The sensitivity of joint use of RT-PCR and RPHI to detect JEV was 100%, higher than using RPHI alone, and was 7.7% higher than using RT-PCR only. RT-PCR is more suitable for epidemiological survey than virus isolation.

This RT-PCR for JEV detection is highly specific and sensitive. Toxemia period of JE patient is very short, so grasping the time of blood specimen collection will affect virus detection rate.