A review and meta-analysis of the epidemiology and clinical presentation of coxsackievirus A6 causing hand-foot-mouth disease in China and global implications.

Coxsackievirus A6 (CV-A6) has been associated with increasingly occurred sporadic hand-foot-mouth disease (HFMD) cases and outbreak events in many countries. In order to understand epidemiological characteristics of CV-A6, we collected the information describing HFMD caused by CV-A6 to describe the detection rate, severe rate and onychomadesis rate, which is defined as one or more nails defluvium, caused by CV-A6 from 2007 to 2017. The results showed that there was an outbreak of CV-A6 every other year, and overall trend of the epidemic of CA6-associated HFMD was increasing in China. The detection rate of CV-A6 in other countries was 32.0% (95% CI: 25.0%~40.0%) before 2013 and 28.0% (95% CI: 20.0%~36.0%) after 2013, respectively. Although the severe rate of HFMD caused by CV-A6 was low (0.10%, 95% CI: 0.01%~0.20%), CV-A6 can cause a high incidence of onychomadesis (28.0%, 95%CI: 21.9%-34.3%). Thus, it would be worthwhile to research and develop an effective multivalent vaccine for CV-A6 to achieve a more powerful prevention of HMFD.