Epidemiologic Characteristics And Prediction On Epidemic Situation Of Bacillary Dysentery In Heping District,Tianjin

Objectives: To explore epidemiologic characteristics and incidence trend of bacillary dysentery from 2004 to 2015 and to predict incidence rate of bacillary dysentery in2016 in Heping district of Tianjin city in order to provide reference for prevention and control strategies of bacillary dysentery.Methods: Bacillary dysentery infection situation and demographic data from 2004 to2015 in Heping district of Tianjin city were collected from the information system of disease prevention and control of China and analyzed for the epidemic characteristics of bacillary dysentery.In addition,one opening intestinal clinic was chosen as a monitoring hospital and an epidemiological survey was conducted,which including all outpatients with bacillary dysentery hospitalized in the intestinal clinic of the monitoring hospital from 2009 to 2014.A total of 7467 outpatients with diarrhea hospitalized in this clinic from 2009 to 2014,and of them,342 patients suffered from bacillary dysentery,accounting for 4.58% of all diarrhea patients.The information of342 patients with bacillary dysentery were collected through an uniform epidemiological questionnaire including information on general situation,clinical characteristics,related factors,medication,economic and family burden.Laboratory data came from outpatients' medical records.An Epi Data database was established and data were analyzed by epidemiological descriptive methods.The incidence rates of bacillary dysentery were calculated as the number of incident patients divided by number of population and compared using chi-square test.Data on the monthly incidence rates of bacillary dysentery from 2004 to 2015 were analysed and the monthly incidence rates of bacillary dysentery in 2016 were forecasted using ARIMA model.Results:1.A total of 2423 patients with bacillary dysentery were reported in Heping district from 2004 to 2015 and the average annual incidence reported was 60.35/100 000,and the highest incidence of bacillary dysentery was in 2005,which was 128.04/100 000,since then,the incidence of bacillary dysentery declined.The incidence rate of bacillary dysentery in male(69.19/100 000)was higher than that in female(51.69/100000),and children aged 0-9 years had the highest incidence rate.The peak incidence was presnt in July and August.The standardized incidence rate by age and sex in Bai Lou community was higher than those in other communities.The top three occupations were students(23.90%),the cadre staff(14.78%)and retirees(12.22%)in the patients with bacillary dysentery.2.The results of epidemiological survey in patients with bacillary dysentery: A total of 7467 outpatients with diarrhea hospitalized in this intestinal clinic of the monitoring hospital from 2009 to 2014.Of them,342 patients suffered from bacillary dysentery(4.58%),3307 patients with infective diarrhea(44.28%)and 3818 patients with non infectious diarrhea(51.14%).The 342 cases of bacillary dysentery,including 169 males and 173 females,were surveyed.The median age was 40 years old and most of them were cadre staff.Cases occur mostly in May to September.83.63% of patients did not take any medicines before attending clinic.Their clinical symptoms included diarrhea,fatigue,loss of appetite,abdominal distention,and fever,etc.and most with watery and mucus stools.2.34% cases had a history of contacting diarrhea patients and 80.12% caces had eaten half raw seafoods.Most cases were treated with norfloxacin.The average medical cost per capita was 286 yuan and had a lesser impact on their family.3.ARIMA(1,1,0)(1,1,0)model built based on the monthly incidence rates of bacillary dysentery from 2004 to 2015 in Heping district shew preferable fitting effect.The prediction results using the model shew that the monthly incidence rate of bacillary dysentery in 2016 will be steadily at low levels and have obvious seasonality with incidence peak of 4.17/100 000 in July,and epidemic trend be consistent with that in the recent decade.Conclusions: The incidence rates of bacillary dysentery in Heping district from 2004 to 2014 decreased gradually and were in low level in recent years with obvious seasonal peak in summer.Children were in high-risk of bacillary dysentery.The main clinical symptom of patients with bacillary dysentery was diarrhea and watery and mucus stools.Most patients have poor eating habits.ARIMA(1,1,0)(1,1,0)model achieved good precision in predicting the incidence rate of bacterium dysentery.