Epidemiology of hand foot mouth disease in Bengbu city, 2008-2016

Objective To explore epidemiological characteristic of hand foot and mouth disease (HFMD) in Bengbu city by analyzing the report and monitoring data for providing scientific basis for prevention and control strategies. Methods We analyzed the monitoring data from 2008 to 2016 in the National Disease Surveillance Information Management System. The swabs of some cases were collected by the sentinel hospital and the detection of intestinal virus nucleic acid was carried out using the method of RT-PCR by the Bengbu center for disease control (CDC). Results A total of 65 464 HFMD including 33 severe cases and 6 fatal cases were reported in Bengbu city from 2008 to 2016, with an average annual incidence rate of 218.48/100 000, 271.32/100 000 in the city and 194.98/100 000 in the country. The city is higher than rural (χ²=189.35, P<0.01). The majority of cases were children below 5 years old, accounting for 96.67% (63 286/65 464). Children under 3 years old accounted for 74.09%(48 502/65 464). There are 13 laboratory diagnosed cases among 33 severe cases. The proportion of cases which had been diagnosed as enterovirus 71 (EV71) positive was 76.92%(10/13). Moreover, the death cases were all confirmed as EV71. Before 2013, EV71 was the only major etiological agents of HFMD in children in every odd-numbered year and in every even-number year EV71 and Cox-A16 were all the major etiological agents of HFMD. However, from 2014 to 2016 the detection rate of other enterovirus increased gradually. The positive rate of nucleic acid detection in clinical cases was 46.62% (1 588/3 406), and there was a statistical difference between the positive rate and the sampling time (χ²=104.292, P<0.01). Conclusion HFMD in Bengbu city has higher level of prevalence, as well as obvious regional, seasonal and crowd high-risk characteristic. EV71 is still the main cause of severe disease and death in HFMD and other intestinal viruses is increasingly becoming the epidemic strain. Case specimens should be collected and submitted as soon as possible.