OBJECTIVETo explore the duration of enterovirus (EV) nucleotides positive in feces samples of hand-foot-mouth disease (HFMD) patients after recovery.

METHODSA consecutive 6-week follow up were carried out towards 49 cases of laboratory-diagnosed HFMD patients. A total of 5 - 8 g feces sample was collected from each patient once a week. The common EV nucleotides of HFMD were detected by RT-PCR method and analyzed by Kaplan-Meier Survival Analysis Method.

RESULTSThe subtypes of the 49 HFMD patients included 16 enterovirus 71 (EV71), 15 coxsackievirus A16 (CoxA16) and 18 EV; a six-week follow up was carried out among all of them. In the first week, one EV71 patient and two EV patients were lost; in the fourth week, one CoxA16 were lost; and in the fifth week, one EV71 patient was lost. During the consecutive 6-week follow-up, the positive rates of EV nucleotides among EV71 patients were 81.3%, 60.9%, 47.4%, 33.9%, 27.1% and 18.1% separately; and the positive rates in CoxA16 group were 93.3%, 73.3%, 53.3%, 33.3%, 16.7% and 8.3% respectively. In EV group, the positive rates of EV nucleotides were 44.4% and 7.4% in the first two weeks and then turned to negative in the next 4 weeks. There was significant statistical difference in positive rates of EV nucleotides among different patients (χ(2) = 11.78, P = 0.001); however, each group of HFMD patients showed a declined trend with the extension of time.

CONCLUSIONThe duration of EV nucleotides positive in feces samples of HFMD patients lasted for a long period since their recovery; and the positive results in EV71 and CoxA16 patients might last for 6 weeks.