Japanese encephalitis is the most common type of viral encephalitis in Hubei province
Objective This study aimed to investigate the pathogen types in patients diagnosed with clinical viral encephalitis(VE)in Hubei province from 2011 to 2023 through laboratory tests,and analyze the epidemiological characteristics of confirmed cases.Methods The serum and cerebrospinal fluid(CSF)samples from reported VE cases were collected in Hubei province from 2011 to 2023.All serum and/or CSF samples of the collected VE cases were screened for Japanese encephalitis virus(JEV)IgM antibodies using the enzyme-linked innunosorbent assay(ELISA),and the detection of the viral genes of JEV using reverse transcription polymerase chain reaction(RT-PCR).Seven other pathogens including herpes simplex virus,mumps virus,coxsackievirus,echovirus,Epstein-Barr virus,cytomegalovirus and varicella zoster virus were detected in serum samples from VE cases excluded from JEV infection.Epidemiological analysis was conducted on laboratory-confirmed cases of VE.Results From 2011 to 2023,ninety-seven VE cases were collected in the Hubei province.The result of serological(JEV-specific IgM)and genetic testing for JEV showed that 64.9%(63/97)of the collected cases were confirmed as JEV infection.Among the thirty-four cases of non-JEV infection,six viruses were detected in the serum of ten cases.The remaining twenty-four cases were classified as unknown VE cases.Our analysis indicated that those aged 0-15 years were the majority of laboratory-confirmed Japanese encephalitis(JE)cases.However,the incidence of these cases in the>40 years age group has increased in recent years.The temporal distribution of laboratory-confirmed cases of JE revealed that the majority of cases occurred from February to September each year,with the highest incidence in July to August.Conclusions JE has been the predominant cause of VE in Hubei province over the past decade.Our findings will provide critical baseline data for the prevention and control of VE in Hubei province.