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In order to meet the needs of prevention and control of intestinal infectious diseases， a comprehensive surveillance for diarrheal diseases has been innovated and explored in Shanghai since 2012. The surveillance has extensive distribution of sentinel hospitals， systematic sampling， multi-pathogen collection， and hospital information system （HIS） as the basis， which has achieved “One system for surveillance of multiple diseases and one sample for detection of multiple pathogens". Continual active surveillance for the whole population has been conducted， covering demography， clinical information， epidemiology， pathogen detection， and drug sensitivity test for diarrhea cases. The surveillance has obtained preliminary achievements as follows. First， diarrheal diseases and their periodic changes have been characterized， in which the most prevalent pathogen of diarrhea is determined to be norovirus in Shanghai. Second， some rare pathogens and serotypes have been identified that may provide clues to the sources of outbreaks. Third， it facilitates the information sharing between public health institutions and clinical institutions， and provides scientific evidence for clinical diagnosis and treatment. In the future， Shanghai diarrhea comprehensive surveillance will be improved for expanding range and depth of surveillance， artificial intelligence assisted diagnosis and treatment， early warning of outbreaks， prediction of epidemic trends， and application of new detection technologies.
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Objective@#To conduct a viral pathogen surveillance program on pediatric inpatients less than five years old with acute gastroenteritis in Shanghai and to better understand the pathogenic spectrum and molecular features in the target population, for setting up programs on control, prevention, medication and vaccine applications of the diseases.@*Methods@#Fecal samples were collected from inpatients less than 5 years old who were admitted to a pediatric hospital for having acute gastroenteritis. Information related to demographic, clinical and epidemiological features of the patients was also collected. Laboratory assays including ELISA, real-time PCR and nested PCR, were performed to detect the presence of pathogens as rotavirus, calicivirus, astrovirus and adenovirus.@*Results@#A total of 1 018 samples were collected (male 671 and 347 female), with the positive detection rate as 40.57% which peaked from autumn till winter, annually. Calicivirus and rotavirus A presented with the highest detection rates (24.75% and 13.95% respectively). The lowest detection rate was found in the 0-6 month-olds (32.20%). 65% of the patients with positive virus had received antibiotic treatment prior to the hospitalization. However, no statistically significant difference was seen, regarding the rates of antibiotic medication in the virus positive or negative populations (P>0.05). Data from the Rotavirus genotype analysis revealed that G9P[8] genotype was the predominant strain, and causing majority of rotavirus infections in all the age groups.@*Conclusions@#Among the inpatients under 5 years of age in Shanghai, the positive detection rate for Calicivirus was higher than that for rotavirus group A, suggesting the necessity to carefully monitor the changes regarding the pathogenic spectrum and subtypes of the virus. Antibiotics should also be attentively administered, together with the development of suitable vaccine.
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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.
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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.
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Objective To introduce the establishment of Shanghai Diarrhea Comprehensive Surveillance System ,and to analyze the epidemiological and etiological characteristics of infectious diarrhea outpatients in Shanghai based on data of Shanghai Diarrhea Comprehensive Surveillance System .Methods Diarrhea patients were surveyed according to a unified designed questionnaire ,who visited one of 22 adult sentinel hospitals and 4 children sentinel hospitals of Shanghai Diarrhea Comprehensive Surveillance during September 2013 to August 2016 .Stool specimens were collected according to different sampling intervals and detected for 12 bacteria and 5 viruses .Characteristics of diarrhea patients were compared and analyzed .Chi-square test was used for statistical analysis .Results Of 4497 infectious diarrhea patients ,the detection rate of viral infection was 29 .77％ ,of which norovirus infection (16 .33％ ) , rotavirus infection (7 .90％ ) and sapovirus infection (1 .90％ ) were dominated . The detection rate of bacterial infection was 15 .38％ ,diarrheagenic E .coli (DEC) infection (5 .25％ ) ,V . parahaemolyticus infection (4 .27％ ) and Salmonella spp .infection (3 .13％ ) .Mixed infection accounted for 11 .07％ .The detection rate ,the infection types and the predominant pathogens in different age groups were statistically different (χ= 18 .11 ,61 .86 and 449 .52 ,respectively ,all P< 0 .01) .DEC ranked first in 3 - 14 years age group , and norovirus ranked first in all other age groups .The pathogen spectrum of infectious diarrhea patients≥ 15 years old showed obvious seasonal changes ,with mainly bacterial infection in summer (peaked in August ,accounting for 81 .56％ ) and mainly viral infection in winter (peaked in January ,accounting for 95 .27％ ) .Norovirus ranked first through the year ,except January ,June ,July and August .Among patients ≥ 15 years old , abdominal pain , fever and loose stools were main symptoms in bacterial infections .Vomiting and watery stool were main symptoms in viral infections . Loose stools appeared frequently in patients ≤ 14 years old .Conclusions Diarrhea Comprehensive Surveillance System based on scientific design and rational distribution is beneficial for understanding the epidemic trends and pathogen characteristics of diarrhea .Viral infections are predominant in infectious diarrhea patients in Shanghai . Norovirus and rotavirus are the most common diarrheal pathogens .The pathogen spectrum of infectious diarrhea patients shows obvious seasonal changes .DEC is common in diarrhea patients ≤ 14 years old . The clinical symptoms of infectious diarrhea caused by different pathogens are different . Targeted preventive measures should be taken for infectious diarrhea of different ages ,different pathogens ,and in different seasons .
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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.
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Objective To understand the epidemiologic characteristics of confirmed and suspected norovirus outbreaks in Shanghai during 2010-2014.Methods The investigation reports of confirmed and suspected norovirus outbreaks in Shanghai from 2010 to 2014 were analyzed.Results A total of 80 norovirus outbreaks, involving 2 399 cases, were reported during this period, and the overall attack rate was 4.17％.The median of the outbreak duration was 4.5 days and the incidence peaked 2 days later averagety for an outbreak.The outbreaks mainly occurred in autumn and winter,53 outbreaks occurred during October-February, accounting for 66.25％.Seventy five outbreaks occurred in schools, child care settings and nursing houses, accounting for 93.75％.The attack rates in hospitalized patients and the elders in nursing houses were higher than those in pre-school and school aged children, the differences were statistically significant (x2=683.12, P＜0.01).The attack rates in medical staff and nurses in hospitals and nursing houses or staff in pre-schools and schools were lower.Vomiting, the main clinical symptom, occurred in 1 900 cases (79.20％), diarrhea and fever developed in 694 cases (28.93％) and 364 cases (15.17％) respectively.The differences were statistically significant (x2 =2 251.48, P＜0.01).The outbreaks were mainly caused by short common exposures and contact with cases.Conclusion The surveillance for norovirus infection should be strengthened in hospitals, schools and others with the crowed during autumn-winter.The protection of risk population should be enhanced.
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<p><b>OBJECTIVE</b>To study the epidemiological characteristics and antibiotic resistance of Salmonella enterica serovar Pomona (S. Pomona).</p><p><b>METHODS</b>Antimicrobial susceptible testing (AST) and pulsed field gel electrophoresis (PFGE) methods were used to analyze on S. Pomona strains that were isolated from diarrhea cases through the diarrhea network monitoring program, environment and food samples in Shanghai as well as from reptiles in Guangxi Zhuang Autonomous Region.</p><p><b>RESULTS</b>4 553 clinic Salmonella (S.) strains were isolated from the Shanghai network laboratories from 2005 to 2012. The top 10 serotypes would include 20 serotypes all belonged to A-F groups, while S. Pomona was next to S. Wandsworth, according to the non- A-F groups. Young children seemed to be susceptible to S. Pomona, and might cause bloody stools and super-infection. The top 10 serotypes from 1 805 foodborne Salmonella strains were significantly more extensive than those from the human S. Pomona strains, followed by those rare serotypes which were mostly isolated from turtle, sea-shellfish and reptiles. Antibiotic resistance of S. Pomona strains from other sources were significantly more severe than those from human samples, and belonged to A and B clones by means of PFGE. Clone A strains were non-epidemic strains which showed multi-drug resistance (MDR) to antimicrobials. Clone B was the main epidemic-causing strain that not resistant to drugs, which consisting B- I from young-age-groups and B-II were from the seniors. B-I strains were homologous to those from shellfish, tortoises and lizards, while B-II strains only showing homology to those from shellfish. One S. Pomona strain-MDR, isolated from human was homologous to 8 antimicrobials.</p><p><b>CONCLUSION</b>S. Pomona was a quite common serotype among those rare serotypes, which showed higher pathogenicity to infants while genetic evolution might take place when comparing them with the strains isolated from the clinics in 2005. Surveillance programs should be intensified along with the early warnings systems on infections which were from seafood and reptiles.</p>