Detection of echovirus 30 causing aseptic meningitis outbreak in Quanzhou and analysis on its genetic characteristics and molecular evolution

Objective To understand the pathogen causing an aseptic meningitis outbreak in Quanzhou in 2011 and pathogen's genetic characteristics and molecular evolution. Methods Clinical specimens were collected from the aseptic meningitis cases to detect enterovirus 71 (EV71), coxsackievirus A16 (Cox A16) and universal RNA by using real-time RT-PCR. The complete nucleotide sequencing of VP1 region of 5 random positive specimens were conducted, BLAST program was used to identify the genotype by nucleotide pairwise-alignment with al1 available sequences in GenBank database, and the phylogenetic tree was drawn to compare with other enterovira1sequences. Results Real-time RT-PCR indicated that 39 of 47 clinical specimens were universal enterovirus positive but not EV71 or Cox A16. The complete nucleotide sequence of VP1 region of 5 enterovirus isolates was 876nt with homology of 98.9%, and had closer relationships with echovirus 30. These strains had close distance with the strains isolated in Henan and Zhejiang in 2008 and far distance with those isolated in Taiwan of China (2001) and India (2011). When compared with echovirus 30 prototype strain Bastianni, the distance was farthest. Conclusion Echovirus 30 circulated in Quanzhou in 2011 and caused aseptic meningitis outbreak in some areas. Phylogenetic trees analyses showed that the strains isolated from this outbreak had close distance with these isolated in China in recent years and far distance with those isolated abroad.