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ObjectiveTo analyze the spatiotemporal characteristics and prevention and control measures of the pandemic caused by the SARS-CoV-2 Omicron variant in Shanghai in 2022， aiming to optimize future prevention and control strategies. MethodsDescriptive statistical method was used to analyze data on daily infections released by the Shanghai Municipal Health Commission from March 1 to June 30， 2022. ResultsAs of 30 June， a total of 627 110 infections and 588 deaths had been reported in Shanghai. Most of the cases were in Pudong New Area （35.47%）， Minhang District （10.18%） and Huangpu District （9.27%）. The cumulative infection rate was 8.78% in Huangpu District， which was the highest among all the districts. With the progress of the pandemic， the prevention and control measures were strengthened from a “precise prevention and control” strategy to “block and grid” screening， and then upgraded to city-wide lockdown. All daily new infections were identified from the quarantined population on April 29， 2022， reaching the goal of “clearance of community transmission”. ConclusionThe cumulative infections in Shanghai exceeded any previous epidemics in mainland China. Given the enhanced transmissibility and vaccine-induced immune escape of the Omicron variant， timely and strong public health measures are needed to suppress the pandemic under the general policy of "Dynamic zero-COVID".
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Objective:To analyze the spatiotemporal characteristics and spatial aggregation of the incidence of hemorrhagic fever with renal syndrome (HFRS) in China from 2004 to 2020, and to provide a scientific basis for prevention and control of HFRS.Methods:The epidemic information of HFRS in China from 2004 to 2020 was collected from the Public Health Science Data Center, the China Health Statistics Yearbook, and the National Statutory Infectious Disease Epidemic Profile Report. The Joinpoint model was used to analyze the annual average incidence rate change trend, ArcGIS 10.5 software was used for spatial visualization analysis, and global spatial autocorrelation, local spatial autocorrelation and spatiotemporal scan analysis were applied to detect hot spots and aggregation areas.Results:From 2004 to 2020, a total of 208 441 cases of HFRS were reported in China, with an average annual incidence rate of 0.91/100 000. Joinpoint model analysis showed that the average annual incidence rate of HFRS in China showed a decreasing trend from 2004 to 2020. In the provinces with high incidence, the disease was mostly distributed with multimodal distribution in spring, autumn and winter, especially in autumn and winter. The results of global spatial autocorrelation analysis showed that the global Moran's I of HFRS incidence rate in China from 2004 to 2019 were all positive. Except 2012 and 2020, the random distribution pattern was not excluded, other years showed spatial clustering ( Z > 1.65, P < 0.05). The results of phased local spatial autocorrelation analysis indicated that Heilongjiang, Jilin and Liaoning provinces were high-high aggregation regions. A total of five aggregation regions were detected in the month-by-month spatiotemporal scan analysis, and the differences of each aggregation region were statistically significant ( P < 0.001). Conclusions:From 2004 to 2020, the overall incidence of HFRS in China shows a downward trend, and the incidence rate has obvious spatial aggregation. High-risk areas still exist, and it is necessary to focus on and take targeted prevention and control measures.
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Objective: The spatial distribution model of particulate matter based on time change in a specific place was established to analyze the spatial and temporal distribution characteristics and movement of particulate matter. Methods: A convenience store was selected as the research subject. The micro-climate and particle number concentration (PNC) of the site were detected, and numerical simulation was carried out by computational fluid dynamics (CFD) simulation method. Based on the discrete phase model, the temporal and spatial distribution characteristics and movement rules of simulated particles were analyzed. Results: The wind speed at the entrance of the convenience store was low and almost unchanged during the detection, while the wind speeds outside and inside outlets were high and changed sharply. The PNC of particle size of 0.02-1.00 μm was higher than that of particle size >1.00 μm (all P<0.05). The PNC with particle size of 0.02-1.00 μm from high to low were checkout counter, entrance, outer outlet and inner outlet (all P<0.05). The PNC of the checkout counter and entrance varies greatly, while the PNC of the outer outlet and inner outlet was relatively steady. The CFD simulation results showed that particles exhaled by individuals near the entrance of the checkout counter of the convenience store could be expelled outdoors more quickly with the influence of airflow. However, particles exhaled by individuals in the middle of the shelves remained suspended indoors for a longer period of time compared to those near the checkout counter. Particles emitted from the air conditioning outlet diffuse throughout the entire store and reach a steady state in 300 seconds. Conclusion: The particulate matter in the convenience store was mainly small particle with the size less than 1.00 μm. The residence time, downward trend and number of suspended particulates of human exhaled particles were related to air flow. The particulates escaped from the air conditioner could quickly spread to almost the entire convenience store.
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BACKGROUND Aedes aegypti is the sole vector of urban arboviruses in French Guiana. Overtime, the species has been responsible for the transmission of viruses during yellow fever, dengue, chikungunya and Zika outbreaks. Decades of vector control have produced resistant populations to deltamethrin, the sole molecule available to control adult mosquitoes in this French Territory. OBJECTIVES Our surveillance aimed to provide public health authorities with data on insecticide resistance in Ae. aegypti populations and other species of interest in French Guiana. Monitoring resistance to the insecticide used for vector control and to other molecule is a key component to develop an insecticide resistance management plan. METHODS In 2009, we started to monitor resistance phenotypes to deltamethrin and target-site mechanisms in Ae. aegypti populations across the territory using the WHO impregnated paper test and allelic discrimination assay. FINDINGS Eight years surveillance revealed well-installed resistance and the dramatic increase of alleles on the sodium voltage-gated gene, known to confer resistance to pyrethroids (PY). In addition, we observed that populations were resistant to malathion (organophosphorous, OP) and alpha-cypermethrin (PY). Some resistance was also detected to molecules from the carbamate family. Finally, those populations somehow recovered susceptibility against fenitrothion (OP). In addition, other species distributed in urban areas revealed to be also resistant to pyrethroids. CONCLUSION The resistance level can jeopardize the efficiency of chemical adult control in absence of other alternatives and conducts to strongly rely on larval control measures to reduce mosquito burden. Vector control strategies need to evolve to maintain or regain efficacy during epidemics.
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Animals , Pyrethrins/pharmacology , Insecticide Resistance/drug effects , Insecticide Resistance/genetics , Aedes/drug effects , Mosquito Vectors/drug effects , Insecticides/pharmacology , Mosquito Control/methods , Aedes/genetics , Spatio-Temporal Analysis , Mosquito Vectors/virology , French Guiana , Insect Vectors/drug effects , Insect Vectors/geneticsABSTRACT
Objective To analyze the genetic characteristics of Legionella pneumophila isolated from cooling water of central air conditioning system in public places in Zhongshan from 2012 to 2018, and to understand the spatiotemporal distribution of homologous strains, in order to provide evidence for the prevention, control and traceability of Legionella pneumophila infection. Methods Eighty-five Legionella pneumophila strains were isolated for serotype identification, and the molecular typing of the 85 isolates was performed using pulsed field gel electrophoresis (PFGE). The strain location data was converted into latitude and longitude coordinates by GIS geocoding technology. The converted location data was overlaid on the map of Zhongshan City, mapping the molecular typing distribution of clusters using Qgis2.18.11 spatial processing software. Results Eighty-five strains of Legionella pneumophila included 9 serotypes, and the highest proportion was LP1, accounting for 61.18% (52/85). According to the similarity of 100%, 85 strains of Legionella pneumophila were divided into 56 patterns of PFGE bands (T1-T56), with 3 types being dominant. Same serotype of Legionella pneumophila strains showed diverse PFGE patterns. Different serotypes of Legionella pneumophila strains were basically identified as different PFGE patterns, while some were identified as same PFGE pattern. According to over 85% similarity, 8 clusters (A-H) were designated, strains of which were distributed in 12 districts. PFGE clustering clusters did not display obvious temporal and regional distribution differences, nor did they have temporal and regional clustering distributions. Conclusion Strains of Legionella pneumophila isolated from cooling water of central air conditioning system in public places in Zhongshan from 2012 to 2018 showed genetic diversity, and the main serotype was LP1. Isolates of clusters did not exist in different years or regions.
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We used the epidemic data of COVID-19 published on the official website of the municipal health commission in Anhui province. We mapped the spatiotemporal changes of confirmed cases, fitted the epidemic situation by the population growth curve at different stages and took statistical description and analysis of the epidemic situation in Anhui province. It was found that the cumulative incidence of COVID-19 was 156/100 000 by February 18, 2020 and the trend of COVID-19 epidemic declined after February 7, changing from J curve to S curve. The actual number of new cases began to decrease from February 2 to February 4 due to the time of case report and actual onset delayed by 3 to 5 days.
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Objective To understand the epidemiological characteristics of scrub typhus and influencing factors in Yunnan province,and provide further information for the prevention and control of scrub typhus.Methods Based on the incidence data of scrub typhus reported in Yunnan from 2006 to 2013,the epidemiological characteristics of scrub typhus were analyzed and related environmental factors were identified with panel negative binomial regression model.Results A total of 8 980 scrub typhus cases were reported during 2006-2013 in Yunnan.The average annual incidence was 2.46/100 000,with an uptrend observed.Natural focus expansion was found,affecting 71.3％ of the counties in 2013.The epidemic mainly occurred in summer and autumn with the incidence peak during July-October.The annual incidence was higher in females than in males.More cases occurred in children and farmers,the proportions of cases in farmers and pre-school aged children showed an obvious increase.Panel negative binomial regression model indicated that the transmission risk of scrub typhus was positive associated with monthly temperature and monthly relative humidity.Furthermore,an "U" pattern between the risk and the increased coverage of cropland and grassland as well as an "inverted-U" pattern between the risk and increased coverage of shrub were observed.Conclusion It is necessary to strengthen the scrub typhus surveillance in warm and moist areas as well as the areas with high coverage of cropland and grassland in Yunnan,and the health education in children and farmers who are at high risk.
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Objective To understand the epidemiological characteristics of scrub typhus and influencing factors in Yunnan province,and provide further information for the prevention and control of scrub typhus.Methods Based on the incidence data of scrub typhus reported in Yunnan from 2006 to 2013,the epidemiological characteristics of scrub typhus were analyzed and related environmental factors were identified with panel negative binomial regression model.Results A total of 8 980 scrub typhus cases were reported during 2006-2013 in Yunnan.The average annual incidence was 2.46/100 000,with an uptrend observed.Natural focus expansion was found,affecting 71.3％ of the counties in 2013.The epidemic mainly occurred in summer and autumn with the incidence peak during July-October.The annual incidence was higher in females than in males.More cases occurred in children and farmers,the proportions of cases in farmers and pre-school aged children showed an obvious increase.Panel negative binomial regression model indicated that the transmission risk of scrub typhus was positive associated with monthly temperature and monthly relative humidity.Furthermore,an "U" pattern between the risk and the increased coverage of cropland and grassland as well as an "inverted-U" pattern between the risk and increased coverage of shrub were observed.Conclusion It is necessary to strengthen the scrub typhus surveillance in warm and moist areas as well as the areas with high coverage of cropland and grassland in Yunnan,and the health education in children and farmers who are at high risk.
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Pseudis minuta is abundant in a variety of aquatic environments of the Pampa domain. Therefore, it can be considered a good model for testing hypotheses on environmental heterogeneity and the influence of climate on the activity of anurans. In this study, we examined the spatial distribution pattern of P. minuta in terms of microhabitats and the influence of abiotic factors on seasonal fluctuations in the abundance of this species. Samples were collected monthly from April 2008 to May 2009 in wetlands and coastal dunes in the Lagoa do Peixe National Park. A total of 112 specimens of P. minuta were collected, of which 45 were found in the wetland area and 67 in the dune area. The species showed seasonal fluctuation in abundance, and it was most abundant in months with higher temperatures (spring-summer). Pseudis minuta was mainly associated with aquatic vegetation, an expected pattern in terms of their morphological adaptations to this environment. Among the abiotic parameters analyzed, only the monthly mean temperature showed a significant correlation (p < 0.05; r = 0.67) with the abundance of P. minuta. We concluded that P. minuta is a generalist species with respect to microhabitat use and also that fluctuation in its population abundance is mainly associated with seasonal variation in temperature.
Pseudis minuta é uma espécie abundante em diferentes tipos de ambientes aquáticos do domínio Pampa. Por essa razão, essa espécie pode ser considerada um bom modelo para testar hipóteses relacionadas à heterogeneidade ambiental e à influência do clima sobre padrões de atividade em anuros. Neste trabalho, foi avaliado o padrão de distribuição espacial de P. minuta em termos de micro-habitats, além de se avaliar a influência de fatores abióticos nas flutuações sazonais da abundância dessa espécie. Coletas foram realizadas mensalmente, entre abril de 2008 e maio de 2009, em áreas úmidas e de cordões de dunas costeiras no Parque Nacional de Lagoa do Peixe. Um total de 112 indivíduos de P. minuta foi coletado, sendo 45 em áreas de banhado e 67 em área de dunas. A espécie apresentou flutuação sazonal na abundância, sendo mais abundantes em meses com temperaturas mais elevadas (primavera-verão). Pseudis minuta esteve associada principalmente à vegetação aquática, um padrão esperado em função de suas adaptações morfológicas a esse meio. Entre os parâmetros abióticos analisados, somente a temperatura média mensal apresentou correlação significativa (p < 0.05; r = 0,67) com a abundância de P. minuta. Foi possível concluir que P. minuta é uma espécie generalista com relação ao uso do habitat e que as flutuações na sua abundância populacional estão principalmente associadas à variação sazonal da temperatura.
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Animals , Anura/physiology , Ecosystem , Anura/classification , Brazil , Conservation of Natural Resources , Fresh Water , Population Density , Population Dynamics , SeasonsABSTRACT
Objective To study the spatiotemporal distribution and seasonal characteristics of influenza and to explore its transmission patterns, in the mainland of China. Methods Spatiotemporal cluster methods and spatial trend surface methods were used to analyze the influenza surveillance data. Results There were a summer peak in the south from June to August (RRpsediatric=1.31, P<0.01; RRmternel=1.74, P<0.01) and a winter peak from December to January (RRpsediatric=1.45, P<0.01; RRmternel=1.45, P<0.01) in the northern part of the country, during every epidemic season. Influenza virus in mainland China seemed to spread from the southern to the northern parts of the country, in a progressing way. Conclusion In the southern part of the country, it is more important to take prevention and control measurements on influenza from June to August but for the northern part, the key period is from December to January. It is more important to timely identify the variation of the influenza virus, in the southern part of the country.