Abstract: objective:To analyze the pathogenic composition of hospitalized children with hand foot mouth disease in Dalian from 2014 to 2016 and monitor the variety of pathogen.Methods:Stool samples were collected from hospitalized children who suffered from hand-foot-mouth disease from June to September during the period of 2014-2016 to extract nucleic acid by magnetic bead column method and to detect the specific RNA nucleic acid fragments by fluorescence PCR.Results:（1） The stool samples of 1 165 cases were collected, 91 cases were negative in intestinal virus test, and 1 074 cases were positive, among which 199 cases in 2014, including EV71 in 48 cases, CA16 in 39 cases and other enterovirus in 112 cases; there were 320 cases in 2015, including EV71 in 37 cases, CA16 in 57 cases and other enterovirus in 226 cases; there were 555 cases in 2016, including EV71 in 127 cases, CA16 in 193 cases and other enterovirus in 235 cases. （2）There were 30 cases complicated by viral encephalitis, 3 cases of negative intestinal virus test and 27 cases positive. Among positive cases, there were 12 cases in 2014, including EV71 in 7 cases, CA16 in 1 case, and other enterovirus in 4 cases; there were 3 cases in 2015, including EV71 in 1 case and other enterovirus in 2 cases; there were 12 cases in 2016, including EV71 in 5 cases, CA16 in 1 case and other enterovirus in 6 cases.（3）There were 12 cases complicated by viral myocarditis, including other enterovirus in 10 cases and CA16 in 2 cases.Conclusion:A pathogenic change has happened in hand-foot-mouth disease in Dalian, with the high frequency of other enterovirus infection, which also contributes to the significantly increasing cases of viral encephalitis or viral myocarditis.

Key words: Hand-foot-mouth disease, Etiology, Enteroviruses, Children