Enterovirus D68 infection in children with acute lower respiratory tract infection in China

Abstract

Abstract Background EV-D68 infection-related acute flaccid paralysis (AFP) has attracted much attention since the outbreak in the USA in 2014. Notably, EV–D68 was detected in a child with acute flaccid paralysis for the first time in China in 2018. Methods Based on a multicentre study monitoring viral pathogens of acute lower respiratory tract infection (ALRTI) in children in China from May 2017 to December 2019, the infection of EV-D68 in children with ALRTI in China was analysed. Results In this study, 10 EV-D68 positive specimens were detected from 3,071 samples collected from patients with ALRTI. These 10 patients presented with mild diseases and no neurological symptoms and signs. The phylogenetic analysis of EV-D68 showed that all 10 EV-D68 sequences obtained in this study belonged to subclade B3 which circulates dominantly worldwide, and shared high identity with sequences of EV-D68 strains obtained from patients with AFP in the USA. Recombination analysis showed that no recombination event was found. Moreover, four EV-D68 strains were successfully isolated and the isolate in this study was able to infect "neuronal-like" cell line SH-SY5Y, which was used to identify the neurotropism of enteroviruses. Furthermore, potential amino acids and nucleotide sites related to EV-D68 neurovirulence were analysed, but according to genetic variation analysis, these reported sites in complete genome may not be enough to explain the neurovirulence of EV-D68. Conclusions EV-D68 infection was detected in a small number of children with ALRTI in China from 2017 to 2019. The genotype of EV-D68 in this study is subclade B3, which can infect the "neuronal-like" cell line SH-SY5Y.