理性看待甲型H1N1流感疫情

继墨西哥、美国、英国、韩国等国相继出现甲型H1N1流感疫情后，2009年5月11日，中国内地也确诊了首例甲型H1N1流感病例。截至6月12日，全球确诊甲型H1N1流感病例已达28774例，我国内地也确诊126例。世界卫生组织警告：甲型H1N1流感比禽流感更可怕。甲型H1N1流感病毒早晚都会发生变异，使甲型H1N1流感能轻易在人与人之间传播，     

人源甲型H1N1流感HA基因进化特征分析

为了探究2009年3月至8月流感大爆发期间的人源甲型H1N1流感病毒的进化特征,提出了一种图形化表达病毒序列的方法,该方法将甲型H1N1流感病毒HA基因的符号序列数字化表达后,利用主成分分析（PCA）将高维数值序列的维度大幅度降低为二维,将低维的数值序列图形化表达在平面和空间中。在序列的图形化表达基础上,对2009年3月到8月收集的三千多个流感病毒样本做了新旧病毒的区分,筛选出了新型病毒菌株,并根据图形探究了甲型H1N1流感病毒在时间序列上的进化特征。     

2009年甲型H1N1流感临床研究回顾

2009年全球爆发的甲型H1N1流感由一种源于猪流感病毒、致人急性呼吸道疾病的新型流感病毒所致.本文总结了甲型H1N1流感病毒感染病例的临床特征、治疗及研究展望.     

甲型H1N1流感病毒病原学特征

自从2009年3月18日墨西哥发现的首例甲型H1N1流感病例以来,在众多国家科研工作者的共同努力下,这种新流感病毒已经开始慢慢向人们揭开面纱。尤其是2009年4月27日公布从美国加利福尼亚州患者身上获得并分离得到的病毒基因序列后,研究人员陆续获得初步研究成果。研究表明：这种病毒基因组由禽流感、猪流感和人流感病毒基因混合而成,是一种新型的甲型H1N1流感病毒,它所引起的流感具有高度传染、传播迅速、易流行的特点。该病毒既有甲型流感病毒的共有特征,也有其特殊性。本文对该病毒的分类与命名、基因组结构特点与变异、相关蛋白及其功能作一综述以便对甲型H1N1流感的诊断、预防、治疗有所帮助。     

甲型H1N1流行与气象因子显著关联

2009年3月18日,墨西哥发现甲型H1N1流感疑似病例:2009年4月21日,美国疾病预防控制中心(CDC)报告2名儿童感染甲型H1N1流感病毒.随后,墨西哥、美国、加拿大等国家出现大量病例,甲型H1N1流感自美洲暴发流行.随着甲型H1N1流感在全球蔓延,世界卫生组织(WHO)将警告级别由3级逐渐提升为6级,表明全球进入流感大流行阶段.截至2010年4月14日,超过213个国家和地区报告了经实验室确诊的甲型H1N1流感病例,至少17770人死亡.     

论科学的体育锻炼在预防H1N1流感的作用

甲型H1N1流感在学校和人群聚集性的地域爆发,并且出现了死亡病例.新一轮甲流疫情在2009年秋冬暗流涌动,面对新一轮汹涌的甲型H1N1流感,更多的还需要我们回到对甲流的防控上来.本文研讨了如何通过体育锻炼未预防甲流的侵蚀.     

一类SIRE对甲型H1 N1流感传播模型的稳定性

收集了我国甲型H1N1流感病毒实验室确认病例数量的数据,对SIR模型进行拓展,借助微分方程解析传染病SIR模型建立SIRE模型,对甲型H1N1流感病毒的传播规律进行研究和预测,得出了决定甲型H1N1流感病毒是否发生的阈值;解析了SIRE对甲型H1N1流感传播模型无病平衡点和地方平衡点的稳定性.     

甲型H1N1流感在美国传播期和墨西哥暴发期的气象条件与中国初夏气候特点的相似分析

2009年5月初,甲型H1N1流感在其发源地墨西哥已得到有效控制,但在美国却快速传播.初步研究表明,气温上升、降水增多对于墨西哥甲型H1N1流感传播趋于平稳和减少起到一定的作用.而纬度较高的美国恰在春夏之交,气温适中、多雨、少光照,气象条件与墨西哥暴发时相似.中国与美国同处于北半球中纬度,6月份中国大部地区气象条件与美国快速传播期地区的气象条件相似,这有可能使得中国的预防和控制期延长.因此,应密切关注中国相似气象条件地区的预防和控制工作,切实做好6月份中国流行性疾病多发易发这一敏感时期的预防和控制工作.     

甲型H1N1流感在预防控制措施下的传播数学模型构建

从数学应用的角度,研究甲型H1N1流感的传播规律,将人群分为易感人群、病毒潜伏人群、发病人群、退出者人群四类. 分析了甲型H1N1流感在人群间的转化过程;日接触率和"聚集性突然爆发"事件被数学刻画,尝试性地构建了一个在预防控制阶段的传播数学模型.     

1例重症甲型H1N1流感产妇的护理

2009年12月13日我科收治重症甲型H1N1流感产妇1例,经积极抗病毒、对症、支持等治疗及精心护理,住院治疗10 d,病情痊愈出院,现将护理体会报告如下。1病例介绍患者女性,20岁,农民,"因咳嗽6 d,发热3 d,呼吸困难25 h"于2009年12月13日01:00入     

Genome evolution of novel influenza A （H1N1 ） viruses in humans

The epidemic situation of A H1N1 flu arose in North America in April 2009, which rapidly expanded to three continents of Europe, Asia and Africa, with the risk ranking up to 5. Until May 13th, the flu virus of A H1N1 had spread into 33 countries and regions, with a laboratory confirmed case number of 5728, including 61 deaths. Based on IRV and EpiFluDB database, 425 parts of A H1N1 flu virus sequence were achieved, followed by sequenced comparison and evolution analysis. The results showed that the current predominant A H1N1 flu virus was a kind of triple reassortment A flu virus： （i） HA, NA, MP, NP and NS originated from swine influenza virus; PB2 and PA originated from bird influenza virus; PB1 originated from human influenza virus. （ii） The origin of swine influenza virus could be subdivided as follows： HA, NP and NS originated from classic swine influenza virus of H1N1 subtype; NA and MP originated from bird origin swine influenza virus of H1N1 subtype. （iii） A H1N1 flu virus experienced no significant mutation during the epidemic spread, accompanied with no reassortment of the virus genome. In the paper, the region of the representative strains for sequence analysis （A/California/04/2009 （H1N1） and A/Mexico/4486/2009 （H1N1）） included USA and Mexico and was relatively wide, which suggested that the analysis results were convincing.     

Influence of extreme weather and meteorological anomalies on outbreaks of influenza A (H1N1)

Biological experiments and epidemiological evidence indicate that variations in environment have important effect on the occurrence and transmission of epidemic influenza.It is therefore important to understand the characteristic patterns of transmission for prevention of disease and reduction of disease burden.Based on case records,we analyzed the environmental characteristics including climate variables in Changsha,and then constructed a meteorological anomaly susceptive-infective-removal (SIR) model on the basis of the results of influenza A (H1N1) transmission.The results showed that the outbreak of influenza A (H1N1) in Changsha showed significant correlation with meteorological conditions;the spread of influenza was sensitive to meteorological anomalies,and that the outbreak of influenza A (H1N1) in Changsha was influenced by a combination of absolute humidity anomalous weather conditions,contact rates of the influenza patients and changes in population movements.These findings will provide helpful information regarding prevention strategies under different conditions,a fresh understanding of the emergence and re-emergence of influenza outbreaks,and a new perspective on the transmission dynamics of influenza.     

2009年加拿大H1N1疫情的ARIMA模型预测与分析

2009年初,世界各地先后发生了甲型H1N1流感.针对加拿大2009年疫情,建立了恰当的ARIMA模型,以实现每日H1N1疫情的预测.经过实证分析,预测的绝对误差在11%以内,总的平均误差是8.39%,该模型成功地对加拿大2009年疫情进行了预测.     

Urban structure and the risk of influenza A (H1N1) outbreaks in municipal districts

Changsha was one of the most affected areas during the 2009 A (H1N1) influenza pandemic in China. Here, we analyze the spatial–temporal dynamics of the 2009 pandemic across Changsha municipal districts, evaluate the relationship between case incidence and the local urban spatial structure and predict high-risk areas of influenza A (H1N1). We obtained epidemiological data on all cases of influenza A (H1N1) reported across municipal districts in Changsha during period May 2009–December 2010 and data on population density and basic geographic characteristics for 239 primary schools, 97 middle schools, 347 universities, 96 malls and markets, 674 business districts and 121 hospitals. Spatial–temporal K functions, proximity models and logistic regression were used to analyze the spatial distribution pattern of influenza A (H1N1) incidence and the association between influenza A (H1N1) cases and spatial risk factors and predict the infection risks. We found that the 2009 influenza A (H1N1) was driven by a transmission wave from the center of the study area to surrounding areas and reported cases increased significantly after September 2009. We also found that the distribution of influenza A (H1N1) cases was associated with population density and the presence of nearest public places, especially universities (OR = 10.166). The final predictive risk map based on the multivariate logistic analysis showed high-risk areas concentrated in the center areas of the study area associated with high population density. Our findings support the identification of spatial risk factors and high-risk areas to guide the prioritization of preventive and mitigation efforts against future influenza pandemics.     

2009年成都市学校甲型H1N1流感暴发疫情流行特征与控制措施评价

目的:了解2009年成都市学校甲型H1N1流感(简称甲流)暴发疫情流行特征,掌握发病规律,评价控制措施,为今后采取更有效的防控措施提供科学依据。方法:收集整理市、区两级疾控机构处置学校甲流暴发疫情资料,对学校按大、中、小学进行分层随机抽样,并进行流行病学分析。结果:2009年成都市学校甲流暴发疫情时间主要集中在9～10月,中、小学生发病高于大学生,预防性服药(中药)和疫情早期及时停课是有效控制措施。结论:学校甲流暴发疫情控制的关键点在于根据实际情况及时、果断地采取相应防控措施。     

Influenza A （HIN1） transmission by road traffic between cities and towns

Influenza A (H1N1) was spread widely between cities and towns by road traffic and had a major impact on public health in China in 2009. Understanding regulation of its transmission is of great significance with urbanization ongoing and for mitigation of damage by the epidemic. We analyzed influenza A (H1N1) spatiotemporal transmission and risk factors along roads in Changsha, and combined diffusion velocity and floating population size to construct an epidemic diffusion model to simulate its transmission between cities and towns. The results showed that areas along the highways and road intersections had a higher incidence rate than other areas. Expressways and county roads played an important role in the rapid development stage and the epidemic peak, respectively, and intercity bus stations showed a high risk of disease transmission. The model simulates the intensity and center of disease outbreaks in cities and towns, and provides a more complete simulation of the disease spatiotemporal process than other models.     

2002-2018年北京市通州区城市热岛(冷岛)效应时空分异规律及其影响因素

北京市通州区于2015年正式成为首都市副中心。截止至2018年,已有大量的人口、工业、商业迁入通州区,使得人为活动大大增加。人为活动以及下垫面的变化会影响通州区地表温度的时空分布。为了给通州区今后的发展进行指导,本文通过MODIS数据和气象数据,得到北京市通州区城市热岛（冷岛）效应的时空分异规律,分析了地表温度和归一化植被指数（NDVI）及气象要素之间的关系。结果表明：北京市通州区1951~2018年的四季气温呈显著上升趋势;城市热岛（冷岛）与环境要素关系密切,归一化植被指数与地表温度呈显著负相关,这表明通州区的植被分布对热场具有调节作用;城市热岛比例指数与平均气温、平均相对湿度呈负相关（相关系数分别为0.012和0.119）;城市冷岛比例指数与平均气温、最大风速呈正相关（相关系数分别为0.186和0.089）。说明随着通州区平均气温的升高,通州区热岛现象减弱,城市冷岛现象增强。通州区最大风速的增加对城市冷岛现象有增强作用。通州区平均相对湿度的增加对城市热岛现象有削弱作用。可见该研究结果可以为北京市通州区城市规划和生态城市建设提供依据。     

Special features of the 2009 pandemic swine-origin influenza A H1N1 hemagglutinin and neuraminidase

Since the 2009 pandemic H1N1 swine-origin influenza A virus (09 S-OIV) has reminded the world about the global threat of the ever changing influenza virus,many questions regarding the detailed re-assortment of influenza viruses yet remain unanswered.Influenza A virus is the causative agent of the pandemic flu and contains 2 major antigenic glycoproteins on its surface:(i) hemagglutinin (HA);and (ii) neuraminidase (NA).The structures of the 09 S-OIV HA and NA proteins (09H1 and 09N1) have recently been resolved in our laboratory and provide some clues as to why the 09 S-OIV re-assortment virus is highly infectious with severe consequences in humans.For example,the 09H1 is highly similar to the HA of the 1918 influenza A pandemic virus in overall structure and especially in regards to its 5 defined antibody binding epitopes.For 09N1,its most distinctive feature is the lack of a 150-loop active site cavity,which was previously predicted to be present in all N1 NAs,and we hypothesize that the 150-loop may play a important role in the substrate specificity (α2,3 or α2,6 linked sialic acid receptors) and enzymatic mechanism of influenza NA.Combination of the HA and NA with special characteristics for the 09 S-OIV might contribute to its high increased transmissibility in humans.