Molecular detection and sequence analysis of enteroviruses isolated from a suspected outbreak of aseptic meningitis

Objective To detect and analyze enteroviruses causing suspected aseptic meningitis in a kindergarten in Jinhua City, Zhejiang Province. Methods Viral RNA was extracted from samples and cDNA was prepared by reverse transcription. PCR was performed to amplify the partial sequences of the 5′-untranslated region (UTR) and VP1 gene of enteroviruses. Serotypes of the viruses were determined by comparing the homology between the partial sequences of VP1 gene. Phylogenetic tree of the partial VP1 sequences was constructed using MEGA6. Results This study included seven patients and twenty-six asymptomatic students. Coxsakievirus A10 (CV-A10) was detected in 48.5% of the students and echovirus 6 (Echo 6) in 21.2%. Besides, 12.1% of the students might be co-infected by the two viruses. Among the seven patients, six were infected by CV-A10 and the other one might have co-infection. According to the phylogenetic analysis, CV-A10 strains detected in this study were closely related to those isolated in China in recent years, including the strains isolated in Xiamen in 2015 and Yunnan in 2017, while the Echo 6 strains were phylogenetically related to those isolated in Yunnan, Guangzhou and Shandong in 2014. Conclusions CV-A10 and Echo 6 were detected in the cases with suspected aseptic meningitis and had close phylogenetic relationships to the strains appeared in China in recent years. Key words: Aseptic meningitis; Enterovirus; Coxsackievirus A10; Echovirus 6