OBJECTIVEProviding evidences for further modification of China Infectious Diseases Automated-alert and Response System (CIDARS) via analyzing the outbreak detection performance of Moving Percentile Method (MPM) by optimizing thresholds in different provinces.

METHODSWe collected the amount of MPM signals, response results of signals in CIDARS, cases data in nationwide Notifiable Infectious Diseases Reporting Information System, and outbreaks data in Public Health Emergency Reporting System of 16 infectious diseases in 31 provinces in Chinese mainland from January 2011 to October 2013. The threshold with the optimal sensitivity, the shortest time to detect outbreak and the least number of signals was considered as the best threshold of each disease in Chinese mainland and in each province.

RESULTSAmong all the 16 diseases, the optimal thresholds of 10 diseases, including dysentery, dengue, hepatitis A, typhoid and paratyphoid, meningococcal meningitis, Japanese encephalitis, scarlet fever, leptospirosis, hepatitis, typhus in country level were the 90(th) percentile (P90), which was the same as provincial level for those diseases.For the other 6 diseases, including other infectious diarrhea, influenza, acute hemorrhagic conjunctivitis, mumps, rubella and epidemic hemorrhagic fever, the nationwide optimal thresholds were the 80th percentile (P80), which was different from that by provinces for each disease. For these 6 diseases, the number of signals generated by MPM with the optimal threshold for each province was decreased by 23.71% (45 557), 15.59% (6 124), 14.07% (1 870), 9.44% (13 881), 8.65% (1 294) and 6.03% (313) respectively, comparing to the national optimal threshold, while the sensitivity and time to detection of CIDARS were still the same.

CONCLUSIONOptimizing the threshold by different diseases and provinces for MPM in CIDARS could reduce the number of signals while maintaining the same sensitivity and time to detection.

China ; Communicable Diseases ; Disease Notification ; Disease Outbreaks ; prevention & control ; Humans ; Population Surveillance ; methods

OBJECTIVETo analyze the implement performance of China Infectious Diseases Automated-alert and Response System (CIDARS) of 31 provinces in mainland China, and to provide the evidences for further promoting the application and improvement of this system.

METHODSThe amount of signals, response situation and verification outcome of signals related to 32 infectious diseases of 31 provinces in mainland China in CIDARS were investigated from 2011 to 2013, the changes by year on the proportion of responded signals and timeliness of signal response were descriptively analyzed.

RESULTSA total of 960 831 signals were generated nationwide on 32 kinds of infectious diseases in the system, with 98.87% signals (949 936) being responded, and the median (the 25(th) percentile to the 75(th) percentile (P25-P75) ) of time to response was 1.0 (0.4-3.3) h. Among all the signals, 242 355 signals were generated by the fixed-value detection method, the proportion of responded signals was 96.37% (62 349/64 703), 98.75% (68 413/69 282) and 99.37% (107 690/108 370), respectively, and the median (P25-P75) of time to response was 1.3 (0.3-9.7), 0.8(0.2-4.9) and 0.7 (0.2-4.2) h, respectively. After the preliminary data verification, field investigation and laboratory test by local public health staffs, 100 232 cases (41.36%) were finally confirmed.In addition, 718 476 signals were generated by the temporal aberration detection methods, and the average amount of signal per county per week throughout the country were 1.53, and 8 155 signals (1.14%) were verified as suspected outbreaks. During these 3 years, the proportion of signal response was 98.89% (231 149/233 746), 98.90% (254 182/257 015) and 99.31% (226 153/227 715), respectively, and the median (P25-P75) of time to response was 1.1 (0.5-3.3), 1.0 (0.5-2.9) and 1.0 (0.5-2.6) h, respectively.

CONCLUSIONFrom 2011 to 2013, the proportion of responded signals and response timeliness of CIDARS maintained a rather high level, and further presented an increasing trend year by year. But the proportion of signals related to suspected outbreaks should be improved.

China ; Communicable Diseases ; Disease Notification ; Disease Outbreaks ; prevention & control ; Humans ; Population Surveillance ; methods

Objective To learn the characteristics of morbidity and mortality of notifiable diseases reported in China in 2013.Methods Descriptive analysis method was used to analyze the morbidity and mortality of notifiable diseases in China in 2013,with Microsoft Excel 2010 and ArcGIS 10.0 used to develop statistical charts.Results In 2013,the morbidity of the nationwide notifiable diseases was 473.87/100 000,a decrease of 3％ below the average of the recent 3 years,while the mortality was 1.23/100 000,an increase of 2％ over the average of the recent 3 years.The rate of laboratory diagnosis of the reported cases was 38.4％.Top 5 diseases of the reported incidence were hand foot and mouth disease,other infectious diarrhea,hepatitis B,tuberculosis and syphilis.The death cases reported were mainly AIDS,tuberculosis and rabies.As classified by the transmission route analysis,intestinal infectious diseases accounted for 49％ of the total incidence reported for the year,followed by the blood and sexually transmitted infectious diseases,respiratory infectious diseases,animal and vector borne infectious diseases.According to the pathogenic analysis,virus infectious diseases accounted for 68％ of the total cases,higher than bacterial infectious diseases and animal-borne/vector-borne infectious diseases.In Shanghai,Zhejiang and Jiangsu,human infection with avian influenza A (H7N9) virus was emerging,as epidemic situation of measles,dengue fever and brucellosis were on the rise significantly nationwide,while the morbidity of infectious diseases decreased,namely pulmonary tuberculosis,hepatitis B among others.Morbidity of the top 5 provinces for notifiable infectious diseases were Hainan,Guangxi,Guangdong,Xinjiang and Zhejiang,respectively.Conclusion The proportion of laboratory confirmed cases among totals was still low in 2013.The morbidity of the infectious diseases was higher in western provinces and parts of south-eastern province,the mortality was higher in westem provinces.The emerging human infection with avian influenza A (H7N9) virus,and the high epidemic of measles,dengue fever and brucellosis in some areas had caught the society concerns.

Objective To evaluate the accuracy of human brucellosis diagnosis and reporting in medical institutions in Shanxi province, and understand the performance of clinical doctors to diagnose human brucellosis according to diagnostic criteria. Methods Field investigation was conducted in 6 medical institutions in the key areas of human brucellosis in Shanxi province. The diagnosis data of the reported brucellosis cases in 2015 were collected and reviewed retrospectively for the evaluation of the diagnosis accuracy with systematic sampling method. The database was established with Excel 2010 and the descriptive analysis and statistical test were conducted with software R 3.3.2. Results The diagnosis consistent rate of the 377 brucellosis cases reviewed was 70.8% (267/377), the diagnosis consistent rates in medical institutions at city-level and country-level were 77.0%(127/165) and 66.0%(140/212) respectively, the differences had significance (χ2=5.4, P=0.02). Among the reviewed cases, the diagnosis consistent rate of laboratory diagnosis and clinical diagnosis were 87.1%(256/294) and 13.3%(11/83) respectively, and the differences had significance (χ2=170.7, P<0.001) . Among the 21 investigated clinical doctors, the numbers of the doctors who correctly diagnosed the suspected cases, probable cases and lab-confirmed cases were only 3, 0 and 8 respectively. All of the clinical doctors knew that it is necessary to report the brucellosis cases within 24 hours after diagnosis. Conclusion The accuracy of human brucellosis diagnosis in key areas of human brucellosis in Shanxi was low, and the performance of the clinical doctors to diagnose human brucellosis according to diagnostic and case classification criteria was unsatisfied.

Objective: We planned to evaluate the effectiveness of moving epidemic method (MEM) in calculating influenza epidemic threshold of 7 climatic zones in China mainland. Methods: The positive rate of influenza virus was obtained from the National Influenza Surveillance Network System from 2010/2011 to 2017/2018. We divided the 31 provinces into 7 climatic zones according to previous literatures and applied MEM to calculate the influenza epidemic threshold of 2018/2019 influenza season for these climatic zones. Sensitivity, specificity, positive predictive value and negative predictive value were calculated to evaluate the effectiveness of MEM. Results: Pre-epidemic threshold (the positive rate of influenza virus) varied from 9.66% (temperate zone) to 16.36% (subtropical zone) for 2018/2019 influenza season. The gap between pre-epidemic and post-epidemic thresholds was less than 5% except for plateau zone. The sensitivity was 86.16% (95CI:66.81%-98.23%), the specificity was 94.92% (95CI: 91.13%-98.41%), the positive predictive value was 89.87% (95%CI: 84.39%-94.38%), the negative predictive value was 92.96% (95%CI: 84.46%-99.17%). Conclusion Overall, moving epidemic Method performs well in calculating influenza epidemic threshold in China, much better than the previous study.