Nail changes, including onychomadesis (nail shedding) and Beau's line, following hand-foot-mouth disease (HFMD) are a common emergence at the stage of late complications of HFMD. However, the exact mechanism is still unknown. the major cause of onychomadesis following HFMD is that certain novel viruses, mostly CVA6, are virulent and may damage nail matrix. Direct injury caused by cutaneous lesions of HFMD around nail matrix is a minor cause. There are still other virulent HEV which may result in