Risk of enterovirus between hand foot and mouth disease among family members of infected and healthy children in Baoshan District of Shanghai

Objective To understand of risk of hand, foot and mouth disease (HFMD) among family close contacts of infected and healthy children and to provide the basis for HFMD prevention and control.Methods Confirmed cases of HFMD from Baoshan district, onset in Jan 2016 to Dec 2017, were matched with 1 ∶ 1 healthy children from the same area.Family members of the HFMD cases and healthy children were investigated with information on demographic information, living environment and health related behaviors.The stool or anal swabs of all members were detected by real-time RT-PCR.The enterovirus infection rates were compared.Results Among the 76 cases, 45 of 179 (25.14%) family close contacts were enterovirus positive, compared with 9 of168 (5.36%) family members of healthy children.The positive rate was highest among brothers and sisters of infected children (55.56%), followed by parents (25.78%) and grandparents (16.67%) (χ2= 6.05, P = 0.048).The positive rates among family members close contact with cases for more than 6 h per day was highest (34.44%) than those spent < 6 h per day (χ2= 8.33, P =0.004).Enterovirus infection risk among family members closely contact with HFMD cases correlated with living area less than 15 m2 (OR = 2.727, 95%CI: 1.329-5.593), been to crowded places within a week (OR = 6.055, 95%CI: 2.432-15.074), while frequent sun drying mattress (OR = 0.015, 95% CI: 0.003-0.080) showed protective effect.Conclusion The enterovirus infection risk among family members closely contact with HFMD infected children can't be ignored.Management and health education should be strengthened among family close contacts with HFMD cases.