For example, increases in plasma MPO and S100A8/A9 levels have been reported in hand, foot, and mouth disease (HFMD) patients (Li et al., 2014; Wen et al., 2015), and Andro-S was demonstrated to be clinically effective against HFMD by reducing fever and inflammation (Li et al., 2013; Wen et al., 2015; Guoliang et al., 2017). Here, MPO is linked to mouth disorder.