BACKGROUND: Although previous studies have shown that meteorological factors such as temperature are related to the incidence of bacillary dysentery (BD), researches about the non-linear and interaction effect among meteorological variables remain limited. The objective of this study was to analyze the effects of temperature and other meteorological variables on BD in Beijing-Tianjin-Hebei region, which is a high-risk area for BD distribution. METHODS: Our study was based on the daily-scale data of BD cases and meteorological variables from 2014 to 2019, using generalized additive model (GAM) to explore the relationship between meteorological variables and BD cases and distributed lag non-linear model (DLNM) to analyze the lag and cumulative effects. The interaction effects and stratified analysis were developed by the GAM. RESULTS: A total of 147,001 cases were reported from 2014 to 2019. The relationship between temperature and BD was approximately liner above 0 °C, but the turning point of total temperature effect was 10 °C. Results of DLNM indicated that the effect of high temperature was significant on lag 5d and lag 6d, and the lag effect showed that each 5 °C rise caused a 3% [Relative risk (RR) = 1.03, 95% Confidence interval (CI): 1.02-1.05] increase in BD cases. The cumulative BD cases delayed by 7 days increased by 31% for each 5 °C rise in temperature above 10 °C (RR = 1.31, 95% CI: 1.30-1.33). The interaction effects and stratified analysis manifested that the incidence of BD was highest in hot and humid climates. CONCLUSIONS This study suggests that temperature can significantly affect the incidence of BD, and its effect can be enhanced by humidity and precipitation, which means that the hot and humid environment positively increases the incidence of BD.
Beijing/epidemiology* ; China/epidemiology* ; Dysentery, Bacillary/epidemiology* ; Humans ; Humidity ; Temperature

Dysentery, Bacillary ; epidemiology ; Humans ; Molecular Epidemiology ; Shigella ; genetics

To demonstrate and evaluate five different methods in the determination of temporal clustering on infectious diseases. The incidence rates of bacillary dysentery in Jinshui district, Zhengzhou city, Henan province from 2008 to 2010 were analyzed by 5 different methods-Cluster Analysis, Runs Test, Negative Binomial Distribution, Circular Distribution and Concentration Ratio. Through Cluster Analysis, data showed that the epidemic period was from May to Sept. with August as the peak. Runs Test confirmed a cluster of month-incidence in 2008 and 2009 (P < 0.05) and a random distribution in 2010. The Concentration Ratio showed a weakened seasonal incidence cluster to a certain extent by M from 2008 to 2010. The Circular Distribution demonstrated an inclining cluster of time (P < 0.01) and it was on July 11(th) and 29(th), as well on August 24(th) in 2008, 2009 and 2010. In terms of day-incidence, the Negative Binomial Distribution presented a cluster in 2008 and 2010, but with no significant difference in 2009. The five above said methods could flexibly be used in determining the temporal clustering of infectious disease at different occasions.
China ; Cluster Analysis ; Dysentery, Bacillary ; epidemiology ; Humans ; Incidence ; Time Factors

Objective: To understand the epidemiological characteristics of notifiable infectious diseases reported in Beijing in 2021 under the influence of the novel coronavirus pneumonia epidemic prevention and control policy, and provide reference evidence for the prevention and control of notifiable infectious diseases. Methods: Descriptive epidemiological methods were used to analyze the morbidity of notifiable infectious diseases reported in Beijing in 2021, with software R 4.1.2 for data process and ArcGIS 10.8 for visualization. Results: The morbidity of notifiable infectious diseases in Beijing in 2021 was 290.51/100 000, a decrease of 43.29% compared with 2020 and a decrease of 71.45% compared with the average during 2017-2019. The top 5 reported diseases with high morbidity were other infectious diarrhea, influenza, hand foot and mouth disease, pulmonary tuberculosis and syphilis. From the perspective of transmission route, intestinal infectious diseases were the main diseases, accounting for 50.15% (31 898/63 601) of the total cases. From the perspective of pathogens, viral infectious diseases were the main diseases, accounting for 59.63% (25 259/42 356) of the total cases. The laboratory diagnosis rate of notifiable infectious diseases reported in Beijing increased from the average of 16.47% (36 289/220 371) during 2017-2019 to 35.36% (22 490/63 601) in 2021. The laboratory diagnosis rate of parasitic infectious diseases was 83.33%. The districts with high incidence of intestinal infectious diseases were Pinggu, Miyun and Fengtai; Natural foci and insect borne infectious diseases were mainly reported in Yanqing, Mentougou, Fangshan and Daxing. Conclusion: The morbidity of notifiable infectious diseases in Beijing in 2021 showed a decrease trend. The laboratory confirmation rate of reported notifiable infectious disease cases increased, and there were great differences in the laboratory confirmation rate among different diseases. It is very necessary to improve the laboratory confirmation rate of the cases. The diseases with different transmission routes showed different geographical distributions. It is necessary to conduct the targeted prevention and control of infectious diseases in different areas.
Beijing ; COVID-19 ; Communicable Diseases/epidemiology* ; Dysentery ; Humans ; Incidence

Age Distribution ; Child, Preschool ; China ; epidemiology ; Diarrhea ; epidemiology ; microbiology ; Dysentery ; epidemiology ; Female ; Humans ; Incidence ; Infant ; Male

Objective: To characterize the prevalence and genomic epidemiology of Vibrio parahaemolyticus from acute diarrheal patients in Shenzhen City from 2013 to 2021. Methods: Based on the Shenzhen Infectious Diarrhea Surveillance System, acute diarrheal patients were actively monitored in sentinel hospitals from 2013 to 2021. Whole-genome sequencing (WGS) of Vibrio parahaemolyticus isolates was performed, and the genomic population structure, serotypes, virulence genes and multilocus sequence typing were analyzed. Outbreak clusters from 2019 to 2021 were explored based on single-nucleotide polymorphism analysis. Results: A total of 48 623 acute diarrhea cases were monitored in 15 sentinel hospitals from 2013 to 2021, and 1 135 Vibrio parahaemolyticus strains were isolated, with a positive isolation rate of 2.3%. Qualified whole-genome sequencing data of 852 isolates were obtained. Eighty-nine serotypes, 21 known ST types and 5 new ST types were identified by sequence analysis, and 93.2% of strains were detected with toxin profile of tdh+trh-. 8 clonal groups (CGs) were captured, with CG3 as the absolute predominance, followed by CG189. The CG3 group was dominated by O3:K6 serotype and ST3 sequence type, while CG189 group was mainly O4:KUT, O4:K8 serotypes and ST189a and ST189 type. A total of 13 clusters were identified, containing 154 cases. About 30 outbreak clusters with 29 outbreak clusters caused by CG3 strains from 2019 to 2021. Conclusion: Vibrio parahaemolyticus is a major pathogen of acute infectious diarrhea in Shenzhen City, with diverse population structures. CG3 and CG189 have been prevalent and predominant in Shenzhen City for a long time. Scattered outbreaks and persistent sources of contamination ignored by traditional methods could be captured by WGS analysis. Tracing the source of epidemic clone groups and taking precise prevention and control measures are expected to significantly reduce the burden of diarrhea diseases caused by Vibrio parahaemolyticus infection in Shenzhen City.
Humans ; Vibrio parahaemolyticus/genetics* ; Diarrhea/epidemiology* ; Foodborne Diseases/epidemiology* ; Serogroup ; Genomics ; Dysentery ; Vibrio Infections/epidemiology* ; Serotyping

OBJECTIVETo explore the epidemic characteristics of bacterial dysentery in Jinan municipality, and to provide scientific basis for effective strategy for bacterial dysentery control.

METHODSThe epidemiological characteristics of bacillary dysentery in Jinan from 1951 to 2005 were analyzed. A total of 485,333 cases in the span of 50 years were recorded, while the population-based case distribution was less than the total cases due to the data incompleteness during the Cultural Revolution.

RESULTSThe incidence of bacillary dysentery in Jinan has been decreasing by years with average incidence rate of 283.10/100,000. The significant differences were observed among the incidence rates of various ages(chi2 = 14.99, P < 0.05). There were four epidemic peaks, and all the incidence rates were about 1000/100,000. Age of onset mainly concentrated in the 0-4 years old, 20-years old and 30-years old. In terms of occupational distribution, workers accounted for 30.31%, the living-scattered children accounted for 22.71%, and the farmers accounted for 17.90%. The incidence focus was from July to September, which accounted for 71.57%. The peak of incidence emerged in August. The highest incidence in urban was 550.94/100,000.

CONCLUSIONThrough the efforts of several generations of health workers, the incidence of bacillary dysentery in Jinan has been basically brought under control. Further step should be taken for the control of bacterial dysentery in urban areas and the management of bacterial dysentery in rural areas. Moreover, the biological characteristics of F2a should be a focus for the future study.

Child ; Child, Preschool ; China ; epidemiology ; Cyclonic Storms ; Dysentery ; epidemiology ; Female ; Humans ; Male

China ; epidemiology ; Dysentery, Bacillary ; epidemiology ; microbiology ; Humans ; Shiga Toxin ; Shigella ; classification

OBJECTIVETo 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.

METHODSARIMA 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.

RESULTSThe 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.

CONCLUSIONARIMA 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.