[Molecular Detection and Genomic Characterization of Enterovirus D68 among Children with Severe Acute Respiratory Infection in Beijing and Shanghai].

To understand the prevalence and molecular typing of enterovirus D68 among children with severe acute respiratory infection(SARI)in Beijing and Shanghai,259 respiratory samples were collected from in Beijing during 2008-2010,and 441 respiratory samples were collected in Shanghai city between 2013and2014.All the samples were used for the screening of EV-D68 by nest RT-PCR and sequencing, and then EV-D68-positive samples were used for the complete genome sequencing through overlapping PCR. All available EV-D68full-length genomes collected from GenBank were used for phylogenetic analysis and comparison of EV-D68 types prevalent in China and America. One(0.4%)from 259 respiratory samples in Beijing was positive for EV-D68,and 4(0.9%)among the 441 samples from Shanghai were positive for EV-D68.Phylogenetic analysis of full length genome indicated that the EV-D68 prevalent in Beijing belong to Clade A2 and Clade B2,different from the American popular strains(Clade A1,Clade B1,Clade B4 and Clade B5).Partial sequence analysis declared phylogenetic conflict among different gene sequences. We concluded that the prevalence rate of EV-D68 among SARI Children in Beijing and Shanghai currently was lower(5/700;<1%),and the EV-D68 genotype prevalent in China and America belong to different clusters. Partial sequence analysis indicated that intratypic recombinant events may occur in EV-D68 prevalent in China.