Virus shedding varies in patients with HFMD induced by EV71, CA16, CA6

Among patients with hand, foot, and mouth disease (HFMD) released from quarantine, there remain high positive rates of viral shedding, but the duration is not consistent among HFMD patients caused by different serotypes, as indicated by the results of a recent study.

“As the highly contagious HFMD spreads rapidly among children, isolation is the most effective way to control its spread,” the authors said.” However, studies on the duration of virus shedding of the HFMD-related enterovirus and a reasonable quarantine period for HFMD patients are inconsistent.”

A systematic review and meta-analysis were carried out to assess the viral shedding of patients with HFMD caused by Enterovirus 71 (EV71) and coxsackievirus A16 (CVA16), and coxsackievirus A6. Seventeen studies including a total of 626 participants met the eligibility criteria.

In specimens of EV71-related patients, the pooled virus positive rate dropped from 0.79 (p<0.001 for heterogeneity) to 0.38 (p<0.001 for heterogeneity) in the first 5 weeks after onset. A decrease was also observed in the positive rate of CVA16, from 0.91 (p<0.001 for heterogeneity) to 0.29 (p<0.001 for heterogeneity).

In patients with specimens related to CVA16 and coxsackievirus A6, the positive rates were nearly 50 percent in the third week after onset. For EV71-related cases, the 50-percent positive rate appeared in the fourth week.

“Our findings provide comprehensive evidence for a possible flexible quarantine period according to the serotype,” the authors said.