Abstract:ObjectiveTo investigate the incidence of recurrence and occurrence rate of recurrence of handfootandmouth disease (HFMD) in Jiangbei District of Ningbo City between 2012 and 2014, analyze the influencing factors, and provide a scientific basis for the prevention and control of HFMD.MethodsData of HFMD in Jiangbei in 2012-2014 were collected from China Disease Surveillance Information System, immunization data were from Immunization Programme Information System of Ningbo City, the recurrent infectious cases were selected and analyzed by descriptive epidemiological methods.ResultsThe occurrence rate of recurrent HFMD in Jiangbei in 2012-2014 was 5.40%, the median month of patients with single occurrence and recurrence of HFMD were 33.77(20.03,47.83)and 38.26(22.05,54.75)months respectively, median month of patients with the initial occurrence were 23.93(15.87,36.87)months, median of time interval of recurrent HFMD was 10.27(5.23,16.06)months. The occurrence rate of recurrence was the highest in 3 years old group(χ2=37.51,P<0.001). Most were scattered children and children in childcare center. Female was a protective factor of recurrence of HFMD (OR,0.73[95%CI, 0.57-0.92]), while children in childcare center was a risk factor (OR,1.46[95%CI,1.16-1.84]). The median attack rate of recurrence in HFMD group and control group in blocks within 7 days were 10.36(9.29,11.44)/100 000 and 8.95(8.16,9.74)/ 100 000 respectively, there was significant difference(Z=-2.68,P<0.001). Inoculation frequency between recurrent HFMD group and control group was not significantly different (Z=-1.38,P=0.17).ConclusionThe epidemic of recurrence of HFMD was serious in Jiangbei District of Ningbo City between 2012 and 2014, boys and children in childcare center should be paid attention, contacts with patients should be reduced, and targeted prevention and control measures should be carried out.