Résumé
Objective@#To investigate the genetic characteristics of enterovirus A 71 (EV-A71) and etiological features of hand, foot and mouth disease (HFMD) in Qinghai province from 2016 to 2017.@*Methods@#Specimens were collected from HFMD patients in Qinghai province, and detected by real-time reverse transcription-polymerase chain reaction (RT-PCR). For EV-A71 positive samples, virus was isolated and RNA was extracted, and then VP1 coding region was amplified by RT-PCR. The phylogenetic tree was constructed by comparing with other genotypes and sub-genotypes strains of EV-A71.@*Results@#It was shown that 114 strains of EV-A71 were isolated in Qinghai province from 2016 to 2017, which all belonged to genotype C4a, and could be divided to two different lineages by phylogenetic analysis. From 2016 to 2017, the epidemic strains of EV-A71 in the different transmission chains of Qinghai province was closely related to other provinces of China.@*Conclusions@#C4a was the dominant genotype of EV-A71 in Qinghai province from 2016 to 2017, and no other genotype was detected. In addition, EV-A71 isolated from Qinghai province co-evolved with EV-A71 in other provinces of China.