Objective:To examine the infection of the enterovirus and human herpes virus in children with suspected encephalitis.Methods:A total number of 365 suspected encephalitis cases were included in this study from August 2017 to December 2019 in Hunan Children′s Hospital. The clinical samples, the cerebrospinal fluid (CSF), serum, sputum, stool and urine were collected and preserved at-80 ℃condition. The enterovirus (EV) and human herpesvirus (HHV) were examined by a one-step nested reverse transcription PCR(RT-PCR) and a real-time fluorescent quantitative PCR (qPCR), respectively. The positive rate of the two viruses in clinical specimens of children with suspected encephalitis was examined. Among all cases, 132 cases were diagnosed with EV encephalitis or HHV encephalitis.Results:the EV encephalitis were identified in 20.5% (75/365) children with suspected viral encephalitis; whereas HHV encephalitis infection was identified as 15.6% (57/365). Among the 75 cases of EV encephalitis, echo 6 was the main sub-type of these diseases 52.0% (39/75) and others were EV71 (30.7%, 23/75), echo11 (6.7%, 5/75), Coxsackie virus A group 6(CA6, 4.0%, 3/75), echo30 (1.3%, 1/75), echo9 (1.3%, 1/75), echo4 (1.3%, 1/75),Coxsackie virus B group 1(CB1, 1.3%, 1/75))and poliovirus(1.3%, 1/75).Human herpes virus type 6 (HHV6) was the most common pathogen in 57 cases of HHV encephalitis, accounting for 35.1% (20/57).The other pathogens were Cytomegalovirus (CMV, 31.6%, 18/57), Epstein-Barr virus (8.8%, 7/57), Herpes simplex virus 1 (HSV1, 10.5%, 6/57), HSV2 (8.8%, 5/57), and Varicella zoster virus (VZV, 1.8%, 1/57) .The virus in CSF detected significantly earlier than that in serum after onset. Virus could be detected in CSF 2-7 days after onset,but 7-26 days in serum. Conclusions:This study uses nested PCR and qPCR to detect pathogens in clinical specimens of children. This not only expands our understanding of the clinical examination and diagnosis of viral encephalitis in children, but also promotes the method of this study to benefit more children.

Objective: To compare the detection rate of herpes virus and enterovirus (EV) in paired cerebrospinal fluid and serum samples of patients with viral encephalitis. Methods: A total of 109 paired cerebrospinal fluid and serum specimens were collected from patients who were clinically diagnosed with suspected viral meningitis in Children′s Hospital of Hunan from December 2017 to February 2018. One-step nested real-time fluorescence quantitative reverse transcription polymerase chain reaction (RT-PCR) and real-time fluorescence quantitative PCR were used to detect enterovirus and herpes virus respectively and the detection rates of different virus and sample types were analyzed. SPSS 17.0 was used for statistical analysis of the test result . Results: Among the 109 pairs of specimens, the positive rates of human herpes virus type 6 (HHV6), herpes simplex virus-1 (HSV1), Epstein-Barr virus (EBV), cytomegalovirus (CMV) and enterovirus group A type 71(EV-A71) in serum were 7.34%, 4.59%, 7.34%, 9.17% and 10.09%, respectively, and in cerebrospinal fluid were 5.50%, 2.75%, 0, 5.50%, and 6.42%, respectively. The result showed that there were statistically significant differences between the two types of specimens for herpes virus and enterovirus (P<0.05). In cerebrospinal fluid and serum samples, the longest time for EV-A71 positive detection was 2 and 7 days after onset, respectively; the longest time for CMV positive detection was 3 and 26 days after onset, respectively; the longest time for HHV6 positive detection was 7 and 8 days after onset, respectively; the longest time for HSV1 positive detection was both 12 days after the onset; in serum samples, the longest time for EBV positive detection was10 days after onset, but in cerebrospinal fluid, no EBV was detected within 10 days of onset. Conclusions EV-A71 is the most prevalent pathogen causing viral encephalitis in hunan, the overall positive rate of virus in serum samples was higher than that in cerebrospinal fluid samples. Virus stays longer in serum than in cerebrospinal fluid. It is suggested that the time is of great significance for the pathogen detection of children with viral encephalitis, the specimen type can be selected reasonably according to the time of onset.