Hand, foot, and mouth disease (HFMD) caused by enterovirus 71 (EV71) can lead to high morbidity and mortality, and genetic background plays an important role during the disease process. We investigated the association between the single‐nucleotide polymorphism (SNP) rs2564978 of the CD55 gene and susceptibility to and severity of HFMD using the SNPs can multiple SNP typing methods. Soluble CD55 (sCD55) expression was significantly lower in the EV71 HFMD group than in the control group and lower in severe cases than in mild cases (P < .001). Moreover, CD55 rs2564978 (C vs T OR = 1.300, 95% CI, 1.120‐1.509) was associated with the risk of EV71 infection, and genotype TC was related to the severity of the infection (TC vs TT OR = 4.523, 95% CI, 2.033‐10.066). Our results suggest that sCD55 expression and the CD55 polymorphism rs2564978 may influence the susceptibility to and severity of EV71 infection.

Coxsackievirus A16 (CA16) remains the most common causative agent of hand, foot, and mouth disease (HFMD), and is related to high incidence and critical complications.Vitamin D receptor (VDR) activity might affect the outcome of CA16 infection. Our case-