Pathogen surveillance and epidemiology characteristics of hand, foot and mouth disease in Beijing and surrounding areas, 2017-2018

Objective To investigate the epidemic features and etiological characteristics of hand, foot and mouth disease (HFMD) in children in Beijing and surrounding areas from 2017 to 2018. Methods The throat swabs of HFMD cases were collected in Beijing and surrounding area from 2017 to 2018. Real-time PCR was used to detected general enterovirus (EV)-EV71/CA16 (Coxsackievirus A16). The VP1 gene sequences of non-EV71 and non-CA16 enterovirus positive samples were amplified by RT-PCR and the amplicons were sequenced. Nucleotide BLAST was used to identify the species of enterovirus. Results A total of 939 HFMD patients were enrolled in this study, including 2 severe cases. The ratio of male to female was 1.54∶1. The majority of cases were younger than five year sold, which accounted for 75.19%, and the children under three years old accounted for 46.96%. The detection rate of EV was 89.24%(838/939), while the rates were 87.44% (181/207) and 89.75%(657/732) in 2017 and 2018, respectively. In 2017, the main EVs were CA6 (47.51%), EV71 (16.02%), CA16 (7.73%) and non-type EV(27.62%); and in 2018, the main EVs were CA6 (46.88%), CA16 (14.31%) and non-type EV (36.99%). Conclusions CA6 is the main pathogen of HFMD in children in Beijing and surrounding areas from 2017 to 2018, and the detection rate of EV71 was decreased. Therefore, more attentions should be paid for the surveillance for other EV besides EV71 and CA16. Key words: Hand, foot and mouth disease; Epidemiological characteristics; Etiology; Coxsackievirus A6