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Objective: To understand the epidemiological characteristics of diarrheagenic Escherichia ( E. ) coli infection in infectious diarrhea outpatients aged 15 years and older in Shanghai and provide evidence for the development of disease control strategies . Methods: Based on multistage systematic sampling, diarrhea surveillance was conducted in 22 sentinel hospitals in Shanghai, the information about cases' demographic, clinical, and epidemiological characteristics were collected. Stool samples were collected for the detection and typing of diarrheagenic E. coli by local centers for disease control and prevention. The positive rate of diarrheagenic E. coli in different populations and seasons from 2014 to 2021 were analyzed. Statistical analysis was conducted by using χ 2 test. Results: In 15 185 diarrhea cases, 8.05% (1 222/15 185) were positive for diarrheagenic E. coli . The positive rate was higher in men (8.74%, 684/7 824) than in women (7.31%, 538/7 361). The positive rate was highest in age group 15-29 years (9.14%, 335/3 665) and the annual positive rate was highest in 2021 (10.21%, 83/813), the differences were all significant ( P <0.05). In the 1 264 strains of diarrheagenic E. coli analyzed through PCR, enterotoxingenic E. coli was the most frequently identified pathogen (50.24%, 635/1 264), followed by enteroadhesive E. coli (27.93%, 353/1 264), and enteropathogenic E. coli (21.36%, 270/1 264). The positive rate of diarrheagenic E. coli showed obvious seasonality with peak in summer (13.92%, 774/5 562) ( χ 2 =495.73, P <0.001). Conclusions: Diarrheagenic E. coli has become a prominent pathogen in infectious diarrhea cases in Shanghai, the disease can occur all the year round with incidence peak during summer and autumn. Predominant subtypes included enterotoxingenic E. coli , enteroadhesive E. coli and enteropathogenic E. coli . Targeted prevention and control strategies are needed for diarrheagenic E. coli -induced infectious diarrhea in different age groups, seasons and for different types of infections.

Objective: To understand the characteristics and differences of diarrhea-related symptoms caused by different pathogens, and the clinical features of various pathogens causing diarrhea. Methods: Etiology surveillance program was conducted among 20 provinces of China from 2010 to 2016. The acute diarrhea outpatients were collected from clinics or hospitals. A questionnaire was used to survey demographics and clinical features. VFeces samples were taken for laboratory detection of 22 common diarrhea pathogens, to detect and analyze the clinical symptom pattern characteristics of the patient's. Results: A total of 38 950 outpatients were enrolled from 20 provinces of China. The positive rates of Rotavirus and Norovirus were the highest among the five diarrhea-causing viruses (Rotavirus: 18.29%, Norovirus: 13.06%). In the isolation and culture of 17 diarrhea-causing bacterial, Escherichia coli showed the highest positive rates (6.25%). The clinical features of bacterial diarrhea and viral diarrhea were mainly reflected in the results of fecal traits and routine examination, but pathogenic Vibrio infection was similar to viral diarrhea. Conclusion: Infectious diarrhea presents different characteristics due to various symptoms which can provide a basis for clinical diagnosis.

Objective: To analyze the epidemiological characteristics related to Norovirus-associated infectious diarrhea bud events in Shanghai, and to discuss the value of bud events surveillance, so as to help Norovirus-associated infectious diarrhea control, prevention and to improve the surveillance system on bud events. Methods: Data related to 142 Norovirus-associated infectious diarrhea bud events were gathered from 16 districts of Shanghai areas in 2018 and were analyzed. Results: There were 2 peaks, April and November for 142 Norovirus-associated infectious diarrhea bud events reported in 2018. 98.59 % (140/142) of the bud events occurred in schools and kindergartens. 80.28 % (114/142) of the bud events would involve 6-19 cases per each event. The median time duration between the onset date of the first case and the reporting date of the event was 2 days and the median event duration was 7 days. The bud event scale and regional incidence of bud events as well as the reporting timelines were influential factors on the duration of the bud events. Conclusions: Two peaks, spring and winter bud events of the Norovirus-associated infectious diarrhea were seen in Shanghai in 2018. Schools and kindergartens were to be prioritized locations for control and prevention of Norovirus-associated infectious diarrhea bud events. Surveillance system was proved to have contributed to the early detection, reporting and control of bud events.

Objective: To understand the epidemiological characteristics of infectious diarrhea pathogens in Pudong New Areas of Shanghai from 2013 to 2017 to provide evidence for control and prevention of the disease. Methods: From Jan 2013 to Dec 2017, active surveillance program on diarrhea was conducted in 14 sentinel hospitals (three tertiary-level and nine secondary-level, and two primary-level hospitals) in Pudong New Areas of Shanghai, based on location, catchment areas and number of patients. All recruited outpatients were interviewed in hospitals, using a standard questionnaire. Stool specimens were collected and tested for five viral and eight bacterial pathogens. Results: A total of 9 301 cases with infectious diarrhea were included, and the overall positive rate was 55.7 % (5 179). Positive rates of single virus, single bacteria and mixed infections were 26.7 % (2 481), 17.0 % (1 579) and 12.0 % (1 119), respectively. For single infection, the most commonly detected viruses appeared as norovirus (15.4 % , 1 428/9 301) and rotavirus (7.2 % , 667/9 301). The most commonly detected bacteria were diarrheagenic Escherichia coli (6.7 % , 619/9 301) and non-typhoid Salmonella (3.3 % , 305/9 301). The most common mixed infections were caused by virus-bacteria (4.9 % , 459/9 301). Norovirus (17.0 % , 838/4 938) showed the highest positive rates, followed by Escherichia coli (7.2 % , 354/4 938), both seen in the age group of 20-59 years old group. Rotavirus (9.4 % , 178/1 896) and non-typhoid Salmonella (4.9 % , 93/1 896) were the most common pathogens found in the age group of 0-4 years old. The prevalence of norovirus peaked both in spring and autumn. The other peaks were seen as: Rotavirus in winter, diarrheagenic Escherichia coli in summer and non-typhoid Salmonella in summer. Conclusions: Our data showed that the positive rates of infectious diarrhea pathogens were high in Pudong New Areas of Shanghai from 2013 to 2017. The dominant pathogens would include norovirus, rotavirus and diarrheagenic Escherichia coli but with differenct distributions in age groups. Obvious seasonal patterns were also observed.

Objective: To understand the seasonality and etiological characteristics of infectious diarrhea in adults from Shanghai. Methods: Adult patients with diarrhea who had visited the enteric disease clinics in 22 hospitals that carrying on the Diarrhea Comprehensive Surveillance sentinel programs in Shanghai during 2014-2017, were surveyed. Stool specimens were collected according to the different intervals of sampling and detected for 12 bacteria and 5 viruses. Concentration ratio and circular distribution method were used for data analysis. Results: From 2014 to 2017, a total of 9 573 stool specimens were collected from the targeted diarrhea patients ≥18 years old ( n =96 067), through the Shanghai Diarrhea Comprehensive Surveillance program. The positive rate of detection was 46.44%. Seasonal peaks of infectious diarrhea were both seen in summer (bacteria peak, diarrheagenic Escherichia coli and Vibrio parahaemolyticus , etc .) and in winter (virus peak, Norovirus, etc .). Both bacterial and viral infections presented seasonal concentration (Raleigh's test P <0.001) but more obvious with bacterial infection. Viral infection accounted for 60.19% of the cause of infectious diarrhea. The top five predominant pathogens appeared as Norovirus, Rotavirus, diarrheagenic Escherichia coli, Vibrio parahaemolyticus, and Salmonella spp.. Conclusions: Among the adult outpatients with infectious diarrhea in Shanghai, obvious seasonality was seen, with peaks in both summer and winter. Viral infection with Norovirus in particular, appeared as the predominant source of infection. Active, continuous and comprehensive diarrhea-related surveillance programs would be able to monitor the changing dynamic of pathogen spectrum, and lead to the adoption of targeted preventive measures.

Objective: To investigate the epidemiologic characteristics of Norovirus among adult patients suffering from infectious diarrhea in Shanghai, so as to provide evidence for developing related strategies on prevention and control of the disease. Methods: Diarrheal outpatients were monitored at the 'Intestinal clinic' from 22 hospitals involved in the sentinel surveillance program in Shanghai. Information on demographic and epidemiologic features of the patients was collected while data and clinical, fecal specimens were collected and sent to the district CDC for Norovirus detection. Positive rates of Norovirus were also compared in various populations and seasons during 2013-2018. Multivariate logistic regression model was adopted to fit into the comparisons between non-Norovirus and Norovirus groups. Results: 19.28% of the 12 083 diarrheal cases were found to have carried the Norovirus, with GⅡgroup the most commonly identified genotype. Rates of detection was seen higher in males (20.78%) than in females (17.73%). 30-44 year-old were found having the highest positive rate (21.51%). The positive rates were found the highest (23.60%) in the year of 2015. All the above shown differences were statistically significant ( P <0.05). Diarrheal patients affected with Norovirus would present watery stool (75.94%) and vomiting (35.84%). Data from the multivariate logistic analysis showed that factors as: being males, 30-44 years old, officials/clerks, in winter season and with histories of travelling etc ., were related to higher risks on Norovirus infection. Conclusions: Infectious diarrhea caused by Norovirus occurred all year round, with seasonal peaks seen in winter and spring, in Shanghai. Specific prevention and control measures should be taken on Norovirus- caused infectious diarrhea, according to the difference on age, gender and season.

Objective: To study the lag effect of temperature and the source of heterogeneity on other infectious diarrhea (OID) in Zhejiang province, so as to identify related vulnerable populations at risk. Methods: Data on OID and meteorology in Zhejiang province from 2014 to 2016 were collected. A two-stage model was conducted, including: 1) using the distributed lag non-linear model to estimate the city-specific lag effect of temperature on OID, 2) applying the multivariate Meta- analysis to pool the estimated city-specific effect, 3) using the multivariate Meta-regression to explore the sources of heterogeneity. Results: There were 301 593 cases of OID in Zhejiang province during the study period. At the provincial level, temperature that corresponding to the lowest risk of OID was 16.7 ℃, and the temperature corresponding to the highest risk was 6.2℃ ( RR =2.298, 95 %CI : 1.527- 3.459). 16.7 ℃ was recognized as the reference temperature. P(5) and P(95) of the average daily temperature represented low and high temperature respectively. When the temperature was cold, the risk was delayed by 2 days, with the highest risk found on the 5(th) day ( RR =1.057, 95 %CI : 1.030-1.084) before decreasing to the 23(rd) day. When the temperature got hot, the risk of OID occurred on the first day ( RR =1.081, 95 %CI : 1.045-1.118) and gradually decreasing to the 8(th) day. Differences on heterogeneous sources related to the risks of OID in different regions, presented on urban latitude and the rate of ageing in the population. Conclusions: Both high or low temperature could increase the risk of OID, with a lag effect noticed. Prevention program on OID should be focusing on populations living in the high latitude and the elderly population at the low temperature areas.

To investigate the short-term impact of temperature on infectious diarrhea in southeast coastal area of China from 2005 to 2013. Two-stage analysis was used to deal with the data of infectious diarrhea from 41 cities in Zhejiang, Fujian and Guangdong Province. Compared with the P (50) temperature, the risk of infectious diarrhea within lag 0-3 d increased when the temperature was between P (22.8) and P (40.4) or higher than P (51.6). The RR value was highest (1.17, 95% CI: 1.11-1.23) when the temperature is at P (90.1). High temperature could increase the risk of infectious diarrhea in southeast coastal area of China.

Objective: To understand the etiological characteristics of bacterial diarrhea in different areas, including large cities, mid-sized/small cities and rural area, in China. Methods: A cross-sectional surveillance was conducted in 17 provinces of China from 2010 to 2014. The acute diarrhea outpatients were selected from clinics or hospitals in large cities, mid-sized/small cities, including rural-urban fringe zones, and rural areas. The demographical and clinical characteristics of the patients were collected by using questionnaire, and stool samples were taken from them for laboratory detection of 17 kinds of bacteria. The differences in pathogen positive rates (PPR) and pathogen spectrum across the cases from three-type areas were compared. The different infection risk in different cases were analyzed with unconditional logistic regression model. Results: In our study, we enrolled 9 253 cases from large cities, 5 138 cases from rural areas and 13 683 cases from midsized/small cites. The pathogen with largest differences in infection rate across the three-type areas was Shigella ( S .) flexneri (rural area: 5.81 % , mid-sized/small city: 2.78 % , large city: 0.46 % ), followed by Aeromonas ( A .) hydrophila (rural area: 2.14 % , mid-sized/small city: 0.96 % , large city: 0.48 % ). Compared with cases in large cities, the cases in mid-sized/small cities and rural areas had higher infection risks for S. flexneri (mid-sized/small city: OR =6.481, 95 %CI : 4.666-9.002, rural area: OR =11.304, 95 %CI : 8.018-15.938) and A . hydrophila (mid-sized/small city: OR =1.992, 95 %CI :1.401-2.832, rural area: OR =4.083, 95 %CI : 2.833-5.884). The constituent ratio of diarrheagenic Escherichia coli and Salmonella increased with the urbanization development, while the ratios of Shigella and A . hydrophila had an opposite trend. S. sonnei (60.00 % ) was the predominant serogroup of Shigella in urban infections, while S. flexneri (77.37 % ) was the predominant serogroup in rural infections. Conclusion: The differences in pathogen spectrum of bacterial diarrhea were obvious across large cities, mid-sized/small cities and rural areas in China, especially the differences in the infection rates of S. flexneri and A. hydrophila.

Objective: To analyze the pathogen spectrum and epidemiological characters of infectious diarrhea cases in Shanghai from July 2013 to June 2015. Methods: From July 2013 to June 2015, using multi-stage sampling to select 22 hospitals as adult diarrhea surveillance sentinels, and 3 district central hospitals together with Shanghai municipal children's hospital as children diarrhea surveillance sentinels. A total of 6 267 diarrhea cases were sampled. The demographic characters, main clinical manifestations and signs of cases were investigated, and stool specimens were collected to conduct the bacteria culture and virus nucleic acid detection. The difference of positive rate of bacteria and virus in different seasons, and age difference of relevant pathogens were compared. Results: Among 6 267 cases, 3 262 (52.05%) were male, and most of them were in 50-69 years group (1 999 cases, 31.90%) and 30-49 years group (1 691 cases, 26.98%). Totally, 2 783 positive specimens were detected out of 6 267 specimens with the positive rate being 44.41%. A total of 7 kinds of bacteria and 5 kinds of viruses were detected. The positive rate for bacterium was 12.61%(790 cases), mainly being vibrio parahaemolyticus (256 cases), diarrheagenic E.coli (239 cases) and salmonella (209 cases). The positive rate for virus was 31.80% (1 993 cases), mainly being norovirus (1 172 cases) and rotavirus (546 cases). The positive rates of viruses in winter of 2013 and 2014 were 57.89%(429 cases) and 62.14%(522 cases) respectively, higher than those of bacterium in the same periods which were 2.43% (18 cases) and 2.86% (24 cases) respectively. The positive rates of bacterium in summer of 2013, 2014 and 2015 were 14.56% (97 cases), 25.29%(258 cases) and 21.21% (49 cases), also higher than those of viruses in the same periods which were 7.51% (50 cases), 8.43%(86 cases) and 11.69% (27 cases) respectively, all of the above differences were statistically significant ( P< 0.05). The cases of 50-69 years group had the highest positive rate of pathogen, which was 47.57% (951/1 999). Secondly was those of 30-49 years group with 47.13% (797/1 691). Positive rate of pathogen for cases of 0-2 years group was 35.74% (213/596). Conclusion: The pathogen spectrumes of infectious diarrhea in Shanghai are mainly vibrio parahaemolyticus, diarrheagenic E.coli, salmonella, norovirus and rotavirus. The summer and winter season peak was obvious. Specific etiological surveillance and control strategies should be strengthened aiming at focus groups including children and the elderly in different seasons.

Objective: To analyze the current situation on infectious diarrhea other than cholera, dysentery, typhoid and paratyphoid (hereinafter referred to as Other Infectious Diarrheal Diseases) under the current monitoring program in China from 2014 to 2015, to provide evidence for developing strategies related to the control of these diseases. Methods: All the reported infectious diarrhea cases and information on public health emergencies relevant to infectious diarrhea were collected from the "Chinese Information System for Disease Control and Prevention" . Analytic method was carried out to describe the etiological and epidemiological characteristics of all the infectious diarrhea cases. Results: In 2014, a total of 867 545 infectious diarrhea cases were reported, with the incidence rate as 64.0/100 000. While in 2015, a total of 937 616 infectious diarrhea cases were reported, and the incidence rate was 68.8/100 000. Cases distributed in all provinces of the country, with incidence rates between 3.8/100 000 and 506.7/100 000. Cases involved in all the age groups, with 53.7 % (968 984/1 805 161) of the total reported cases below 5 years of age. Reported cases showed two peaks of incidence, in summer (from June to August) and winter (from November to next January). Laboratory-confirmed cases accounted for 9.5 % (82 285/867 545) of the total and 9.3 % (86 975/937 616) of the cases reported in 2014 and 2015 respectively. Among cases reported in the two years, viral infection accounted for 92.4 % (76 045/82 285) and 91.0 % (79 176/86 975) while bacterial infection accounted for 7.4 % (6 062/82 285) and 8.8 % (7 614/86 975), respectively. Among the death cases, only three were laboratory confirmed, with two of them caused by rotavirus. Conclusions: Children under 5 years old appeared both higher incidence and mortalities for infectious diarrhea. Most laboratory-confirmed cases were viral-born, with pathogenic spectrums varied in different provinces. Capabilities related to testing and case-reporting on infectious diarrheal diseases differed greatly among areas that called for urgent improvement.

This paper summaries the application of adaptive kernel density algorithm in the spatial relative risk estimation of communicable diseases by using the reported data of infectious diarrhea (other than cholera, dysentery, typhoid and paratyphoid) in Ludian county and surrounding area in Yunnan province in 2013. Statistically significant fluctuations in an estimated risk function were identified through the use of asymptotic tolerance contours, and finally these data were visualized though disease mapping. The results of spatial relative risk estimation and disease mapping showed that high risk areas were in southeastern Shaoyang next to Ludian. Therefore, the spatial relative risk estimation of disease by using adaptive kernel density algorithm and disease mapping technique is a powerful method in identifying high risk population and areas.

Objective: To analysis the etiological and epidemiological characteristics of the reported infectious diarrhea (other than cholera, dysentery, typhoid and paratyphoid) cases in China in 2011., Methods: A total of 836 591 reported infectious diarrhea cases were collected from "China Information System for Disease Prevention and Control" since first week to fifty-second weeks in 2011, 59 929 out of which were laboratory-confirmed. The information of thirty public health emergencies relevant with infectious diarrhea was collected from "Emergency Public Reporting System" between first week and fifty-second weeks in 2011. The epidemiological characteristics of reported cases, confirmed cases and outbreaks, and the pathogenic spectrum of confirmed cases were then analyzed., Results: In 2011, 836 591 infectious diarrhea cases (other than cholera, dysentery, typhoid and paratyphoid) were reported, and the incidence rate was 62.39/100 000. More than half patients were children aged under 5 year-old, accounting for 52.13% (436 098/836 591) and the incidence rate was 447.06/100 000 (436 098 cases). Most of the ill children were scattered, accounting for 50.53% (422 752/836 591). Reported cases showed two incidence peaks, with a summer peak from twenty-third weeks to thirty-fifth weeks, accounting for 34.33% (287 231/836 591) and a winter peak from forty-third weeks to fifty-second weeks, accounting for 23.54% (196 939/836 591). Cases distributed all over China, the incidence in Beijing (253.00/100 000 (49 619 cases)), Tianjin (244.34/100 000 (31 614 cases)), Zhejiang (204.42/100 000 (111 257 cases)), Ningxia (132.16/100 000 (9328 cases)) and Guangdong (127.40/100 000 (132 880 cases)) ranked the top five. Among the 30 public health emergencies, 5 outbreaks had lab tested pathogenic results, including 4 were norovirus-induced. Laboratory-confirmed cases accounted for 7.16% (59 929/836 591) of the case reported, including 56 687 viral cases and 3242 bacterial cases. Rotavirus cases took the highest proportion of viral cases, at 97.35% (53 612/55 185); and 97.15% (53 612/55 185) of which were children aged under 5 year-old. 82.42% (45 480/55 185) of the cases distributed in Guangdong and Zhejiang province, with the incidence peak from fiftieth weeks to fifty-first weeks, accounting for 15.42% (8508/55 185) of the whole year cases. The main pathogens of bacterial diarrhea were Salmonella, Vibrio parahaemolyticus and Escherichia coli, accounting for 48.43% (1570/3242), 32.20% (1044/3242) and 8.57% (278/3242) respectively, with the incidence peak from thirty-first weeks to thirty-fifth weeks, accounting for 23.01% (746/3242). Salmonella infection patients were mainly from Shanghai, Guangdong and Zhejiang province (91.59% (1438/1570)), Vibrio parahaemolyticus patients were mainly from Shanghai (80.94% (845/1044)), and Escherichia coli patients were mainly from Guangdong province (84.17% (234/278)). Salmonella patients were concentrated in 0-9 years group, accounting for 42.36% (665/1570), while Vibrio parahaemolyticus patients in 20-39 years group, accounting for 81.99% (856/1044), and Escherichia coli patients in under 1 year old and 20-39 years group, accounting for 63.67% (177/278)., Conclusion: In China, children aged under 5 year-old should be the priority population in surveillance of infectious diarrhea. Rotavirus is the main pathogen causing infectious diarrhea. The lab-testing and case-reporting capabilities differed greatly among areas.

Objective: To understand the spectrum of diseases and epidemiological characteristics of outpatients at Entric Disease Clinic, with a focus on analysis of the distribution of infectious diarrheal diseases in different populations and to explore disease control strategies on Enteric Infectious Diseases for focal groups., Methods: A census on outpatients at Entric Disease Clinics was conducted in two class Three comprehensive hospitals in Beijing from April 1 to October 31, 2009 based on a descriptive study using diarrhea-syndrome surveillance system set in the two clinics, thus to depict the spectrum of diseases and epidemiological characteristics of outpatients, and analyze the proportion of infectious diarrhea in diarrheal diseases specifically and the rate changes of infectious diarrhea in different months, age groups and occupational groups., Results: Diseases are varied at the two enteric diseases clinics among the patients and there are mainly 10 kinds of diseases, "non-infectious diarrhea" accounted for the highest percentage (77.4%), followed by "unspecified diarrhea" (11.7%), and infectious diarrhea accounted for the least proportion(8.7%)."Gastroenteritis and enteritis" are the most frequently diagnosed cases among all the diseases, was a total of 7 565 cases, accounting for 70.2%. The volume of visits reached its top during summer and autumn(July to September), and the mean volume of visits in this period is (60.78+/-16.85) cases/day. The volume of visits has an obvious seasonal trend, and visits during July and August are the most frequent (41.82% altogether). Patients with "infectious diarrhea" had a highest ratio(5.3%) in May and lowest (1.1%) in October while patients with "bacillary dysentery" accounted for a highest ratio(8.2%) in September and lowest(3.8%) in April. Outpatients are mainly from Beijing city(61.9%), in which young and middle-aged people accounted for 73.9% in total, and student is the main occupation (28.8%). The distributions of diarrheal diseases are the same in different age groups but differ from different occupational groups. Infectious diarrhea accounted for a highest proportion(9.2%) in 18-to-44-year-old age group when using age grouping, and a highest proportion(15.2%) in restaurant service personnel when using occupation grouping., Conclusion: The volume of outpatients attended at general hospitals is overwhelming especially in July and August, and the major type is "non-infectious diseases", which indicates an arduous task on prevention and control of Enteric Infectious Diseases. Infectious diarrhea took up a certain amount, but the rate is not that high, which indicates possible missing diagnosis of patients with infectious diseases.Our focal groups would be young and middle-aged people and students in the city. Therefore, the need to extend the consultation hours is urgent. Meanwhile, for the main goal of surveillance and early warning on Enteric Infectious Diseases, all aspects of construction of Enteric Disease Clinic should be strengthened, such as enhance laboratory tests on pathogens, improve diagnosis level of physicians and etc.

Objective: To explore the feasibility of establishing and applying of autoregressive integrated moving average (ARIMA) model to predict the incidence rate of dysentery in Shanghai, so as to provide the theoretical basis for prevention and control of dysentery., Methods: ARIMA model was established based on the monthly incidence rate of dysentery of Shanghai from 1990 to 2007. The parameters of model were estimated through unconditional least squares method, the structure was determined according to criteria of residual un-correlation and conclusion, and the model goodness-of-fit was determined through Akaike information criterion (AIC) and Schwarz Bayesian criterion (SBC). The constructed optimal model was applied to predict the incidence rate of dysentery of Shanghai in 2008 and evaluate the validity of model through comparing the difference of predicted incidence rate and actual one. The incidence rate of dysentery in 2010 was predicted by ARIMA model based on the incidence rate from January 1990 to June 2009., Results: The model ARIMA (1, 1, 1) (0, 1, 2)(12) had a good fitness to the incidence rate with both autoregressive coefficient (AR1 = 0.443) during the past time series, moving average coefficient (MA1 = 0.806) and seasonal moving average coefficient (SMA1 = 0.543, SMA2 = 0.321) being statistically significant (P < 0.01). AIC and SBC were 2.878 and 16.131 respectively and predicting error was white noise. The mathematic function was (1-0.443B) (1-B) (1-B(12))Z(t) = (1-0.806B) (1-0.543B(12)) (1-0.321B(2) x 12) micro(t). The predicted incidence rate in 2008 was consistent with the actual one, with the relative error of 6.78%. The predicted incidence rate of dysentery in 2010 based on the incidence rate from January 1990 to June 2009 would be 9.390 per 100 thousand., Conclusion: ARIMA model can be used to fit the changes of incidence rate of dysentery and to forecast the future incidence rate in Shanghai. It is a predicted model of high precision for short-time forecast.

Objective: To determine the pathogen of an unexplained epidemic event of infectious diarrhea by laboratory diagnosis of suspected cases samples., Methods: 28 samples from 28 suspected cases (22 fecal samples, 3 vomitus samples, 3 anus swab samples) were tested for Norovirus by RT-PCR. Sequencing and phylogenetic analysis were acomplished of 5 positive samples., Results: 160 of 5694 population were ill with an attack rate of 2.81%. The peak period was 7-9, March. 14 of 28 samples were tested Norovirus positive.Sequencing and phylogenetic analysis showed Norovirus type GII/4 was the causative agent and it had highest identity (97. 9%) with epidemic strain 2006b., Conclusion: The epidemic event ofinfectious diarrhea were caused by GII/4 Norovirus strains.

Objective: To investigate molecular epidemiologic features of rotaviruses circulating in Shanghai, China., Methods: Stool samples were collected from 1230 hospitalized children with community-acquired and nosocomially acquired diarrhea in Children's Hospital Affiliated to Fudan University between November 1, 1999 and December 31, 2001. Polyacrylamide gel electrophoresis (PAGE) was used to detect rotavirus genomic RNA and identify electropherotypes of group A rotavirus RNAs. Reverse transcription polymerase chain reaction (RT-PCR) was performed to amplify full length VP7 gene and dot blot hybridization was performed to identify rotavirus G serotypes using digoxigenin-labelled variable regions from VP7 genes as probes. These probes were amplified by PCR from recombinant plasmids containing full length G1, G2, G3 and G4 VP7 genes from rotavirus field strains detected in Beijing and digoxigenin labelled dUTP was integrated into the PCR products. The Kruskal-Wallis analysis of variance was employed to analyze whether there were significant differences in variables., Results: Out of 1230 samples investigated, 493 (40.1%) were group A rotavirus gene positive by PAGE, among which 397 (80.5%) showed long electropherotypes, 55 (11.2%) showed short electropherotypes, 18 (3.7%) showed mixed electropherotypes which suggested that the children were co-infected by rotaviruses with different electropherotypes, 23 (4.7%) were non-typable because of degradation of some of the genomic RNA fragments. No group B or group C rotavirus was found. RT-PCRs were performed for 328 fecal specimens containing sufficient rotavirus RNAs and VP7 gene products were obtained from 254 (77.4%) samples. Dot blot hybridization showed serotype G1 accounted for 55.5% (141) of these samples, serotype G3 accounted for 27.6% (70), serotype G2 accounted for 9.4% (24), co-infection by 2 rotaviruses with different G types accounted for 6.3% (16), only 1 G4 was detected and 2 were non-typable. The genomic RNA patterns of all G2 strains were short and those of G1, G3 and G4 strains were long. There were no statistically significant differences for age distribution and clinical manifestations among those infants and children infected by rotaviruses with different G serotypes., Conclusion: Group A rotavirus is the major pathogen for diarrhea in infants and children in Shanghai during the period of Nov. 1999 to Dec. 2001. Rotaviruses with long electropherotype were dominant during these years. Serotypes G1 to G3 constituted 98.8% of all 254 strains tested, and G1 was the most common serotype followed by G3 and G2, whereas serotype G4 was seldom found. Some of the children were co-infected by rotaviruses with different G serotypes. Clinical manifestations were not related to the infecting rotavirus with different G serotypes.

Objective: To investigate the epidemiological characteristus of human caliciviruses (HuCVs) among children under 5 years of age with acute diarrhea and to estimate the disease burden in Lulong county., Methods: HuCVs were detected by enzyme linked immunosorbent assay (ELISA) and reverse transcription-polymerase chain reaction (RT-PCR). Some PCR amplicons were cloned and sequenced. Phylogenetic tree was constructed for strain characterization. The rate of HuCVs-attributed hospitalization was estimated according to the positive rate of HuCVs detection in fecal specimens collected from hospitalized diarrhea patients., Results: Between July 1999 and June 2001, 708 fecal specimens were collected, of which 393 rotavirus-negative and 5 rotavirus-positive specimens were detected for HuCVs. Thirty-one point six percentage of fecal specimens from patients with diarrhea was HuCVs positive. Among inpatients, HuCVs positive rate was 17.5%. HuCVs detection was mainly distributed in 3 - 17 mouth-old children, in winter. All 11 strains belonged to NLV GII in which 6 strains GII-3, 2 strains GII-4 and 3 strains GII-7, and they shared 55.1% - 100% nucleotide identity. NLV GII-4 and GII-7 were identified in 2000, while NLV GII-3 and GII-7 in 2001. The preliminary estimate of HuCVs-attributed hospitalization rate was 3.6 per thousand., Conclusion: Human caliciviruses with different genotypes circulated among children in Lulong county with GII NLVs were the prevalent strains. The disease burden of HuCVs was second to rotavirus.

Objective: To provide information on epidemiology of rotavirus infection in Beijing, China., Methods: An ongoing hospital-based surveillance was conducted among children < 5yr old with acute diarrhea according to WHO generic protocol (CID-98). During a 3-year study (Apr. 1998 to Mar. 2001), a total of 484 stool samples were collected from 1 457 patients, including 275 samples from 1 048 outpatients and 209 samples from 409 inpatients., Results: The overall detection rate of rotavirus infection was 25.4%. Rotavirus was responsible for 27.3% of diarrhea inpatients on a yearly base, and 46.2% during rotavirus season. Two peaks of diarrhea were observed each year, one in the summer (June-Sep.) due to bacterial dysentery (16.7%) and another in fall winter (Oct.-Dec.) due to rotavirus infection (23.0%). The detection rate on rotavirus was the highest in age group of 6 - 11 months (38.2%), followed by 1 - 2 years old (28.5%). Ninety six point eight percentage of children were infected under 3 years of age. The number of deaths, possibly caused by rotavirus diarrhea were accounted for 40% of all diarrhea deaths and 11.1% of the total deaths. Serotyping of 123 rotavirus isolates showed that serotype G1 (55.3%) was predominant, followed by G2 (26.8%), G3 (9.8%), G4 (0.8%), and 10 isolates (8.1%) remained non-typeable. Mixed infections (0.8%) seemed to be rare., Conclusion: Rotavirus diarrhea was an important infectious disease among children in Beijing. Safe and effective rotavirus vaccines for the prevention of severe diarrheas and the reduction of treatment costs are of significant importance to China.

The incidence rates of infectious diseases were selected and analysed according to data from the Beijing Railway Area during 1981-1991. We put forward the mathematical model to forecast the incidence rate of dysentery each quarter in 1992. The best mathematical model was selected from analysis of precision, and very useful in the prevention and treatment of seasonal infectious diseases.