Etiology and epidemiology of hand foot and mouth disease in Yinzhou district, Ningbo,2011-2013

Objective To analyze the etiological and epidemiological characteristics of hand foot and mouth disease(HFMD)in Yinzhou district of Ningbo, Zhejiang province. Methods A total of 1015 clinical samples were collected from HFMD cases from 2011 to 2013 to conduct etiological detection. The incidence data of HFMD in Ningbo were collected from national disease reporting information system for descriptive epidemiological analysis. Results The predominant virus varied during the three years, i.e. EV71 in 1st-3rd quarters 2011,Cox A16 in 4th quarter 2011 and in 2nd quarter 2012,and Cox A6 in 3rd quarter 2012 and in 4th quarter 2013. The incidence varied with season obviously and the incidence of severe HFMD was highest in 2011. The incidence varied with season obviously and the number of case clustering was highest in 2012. The seasonality of HFMD was not obvious in 2013. Conclusion The epidemic caused by EV71 and Cox A16 might have obvious seasonality. The pathogenicity of EV71 was highest, the transmissibility of Cox A16 was strongest. Cox A6 could cause the disease throughout the year. With the increase of other human enterovirus, the re-infection rate increased.