1、传染病流行病学讲讲 授授 内内 容容 Teaching Content 研究传染病的意义研究传染病的意义 传染病流行趋势传染病流行趋势 传染病流行病学基本原理传染病流行病学基本原理 和方法和方法 疫源地疫源地 传染病的预防和控制传染病的预防和控制v study importance v epidemic trendsv basic principles and methods v infectious focusv prevention&control研究传染病的意义研究传染病的意义Study Importance 危害严重危害严重重治轻防,后果惨重重治轻防,后果惨重死灰复燃死灰复燃新发传染病
2、不断出现新发传染病不断出现生物恐怖威胁存在生物恐怖威胁存在FSeriously burden of diseasesFNeglect of prevention,the consequences of heavyFThe resurgence of relapseFThe new emerging infectious diseases FThreat of bioterrorism 新出现的传染病新出现的传染病(emerging infections or emerging infections or emerging infectious diseasesemerging infectio
3、us diseases,EIDEID)是指是指新确定的和先前未知的可引起局部或在世界范围内新确定的和先前未知的可引起局部或在世界范围内公共卫生问题的传染病。公共卫生问题的传染病。-David David HeymannHeymann 19971997“emerging infections emerging infections”refers to newly refers to newly identified and previously unknown infectious identified and previously unknown infectious diseases whi
4、ch cause public health problemsdiseases which cause public health problems,either locally or internationallyeither locally or internationally。c重新出现的传染病重新出现的传染病(re-emerging infectious re-emerging infectious diseasesdiseases)是指那些我们已经熟知的,且其传播水平已降低到不再成为公共卫生问题的感染又重新回复到具有流行程度传播状态的疾病。cRe-emerging infectiou
5、s diseases are infections that have been known about for some time but had fallen to such low levels that they were no longer considered a public health problem。They often reappear in epidemic proportions.新出现的传染病的流行具有某些新出现的传染病的流行具有某些引人注目的特点引人注目的特点 The characteristic of EIDM悄然出现悄然出现 Silent beginning
6、M全球化趋势全球化趋势 Globalization M动物动物人人?Jump of infectious agent across the species barrier from animal to human beingM新出现的病原体通常具有较大的毒力和新出现的病原体通常具有较大的毒力和/或传染性或传染性 More virulent and/or epidemicEIDEID产生的原因产生的原因The cause of EIDI人口数量及人的行为变化人口数量及人的行为变化 The change of population and peoples behaviorI技术进步和工业化时间的变
7、化技术进步和工业化时间的变化 Technological progress and industrializationEIDEID产生的原因产生的原因The cause of EIDI经济发展和土地使用模式的变化经济发展和土地使用模式的变化 Economic development and land-use patterns change I国际旅游、商贸的发展以及人口流动的数量迅速国际旅游、商贸的发展以及人口流动的数量迅速增加增加 The development of International travel,and commerce,and population movementEIDEI
8、D产生的原因产生的原因The cause of EIDI病原生物适应性变异病原生物适应性变异 Pathogens variationI在世界范围内,从地区、国家到全球多个不同层次和在世界范围内,从地区、国家到全球多个不同层次和水平上,因投入大幅下降,而致应对传染病的公共卫生水平上,因投入大幅下降,而致应对传染病的公共卫生能力被削弱,以至破坏能力被削弱,以至破坏 Lack of health resources 其他与其他与EIDEID产生相关的原因产生相关的原因Other causes of EIDI全球气候持续变暖,导致热带、亚热带的范围不断扩大,全球气候持续变暖,导致热带、亚热带的范围不断
9、扩大,直接影响了动植物生态系统,使生物群落、传播疾病的啮直接影响了动植物生态系统,使生物群落、传播疾病的啮齿类动物及昆虫媒介的种属、分布区域和密度等发生改变齿类动物及昆虫媒介的种属、分布区域和密度等发生改变 The global climate continues to warmI生物恐怖主义的潜在威胁生物恐怖主义的潜在威胁 Bioterrorism传染病流行趋势传染病流行趋势 The epidemic trends of Infectious diseaseMajor achievements of infectious diseases prevention and control til
10、l 1970s Total morbidity decreased Total mortality decreased Fatality rate of the majority decreased Modes of Transmission changed Large scale epidemics decreased 总的总的发病率发病率降低降低 总的总的死亡率死亡率降低降低 大多数传染病大多数传染病病死率病死率下降下降 不同不同传播途径传播途径疾病构成改变疾病构成改变 大规模流行减少大规模流行减少全球传染病的主要防治成果全球传染病的主要防治成果Global burden of disea
11、se(DALY)(2000)DALY=Disability adjusted life-yearInjurycommunicableMalnutritionEtc.AfricaEast-Med%755025EuropeAmericaE-S AsiaWest Pacific2000年全球各地区疾病负担(DALY)Reporting data of legal infectious disease in China(1950-2003)0.001000.002000.003000.004000.005000.006000.007000.008000.005053565962656871747780
12、83868992959801morbiditymorbidity(1/100,000)0.0010.0020.0030.0040.0050.0060.00mortalitymortality(1/100,000)Total morbidityTotal morbidityTotal mortalityTotal mortality1950-20031950-2003年全国法定传染病报告情况年全国法定传染病报告情况Leading infectious killers全球传染病的流行现状全球传染病的流行现状100-250/per 100 000Distribution of Tuberculosi
13、s Worldwide(2000)结核病的全球分布(结核病的全球分布(20002000)3%丙型肝炎的全球分布(2000)Distribution of C Hepatitis Worldwide(2000)The HIV epidemic in the Worldwide(2005)全球艾滋病流行现状全球艾滋病流行现状 (2005)(2005)The Morbidity of Main Infectious Diseases in ChinaTB 5 MillionSchistosomiasis 1 MillionHIV 1 MillionHBV 120 Million中国传染病的发病现中国
14、传染病的发病现状状The Reported STD Cases in China432626632307837357853000300466199733235344923413972417552824084836265415710839851285977010000020000030000040000050000060000070000080000090000019851986 1987198819891990 1991199219931994 1995199619971998 199920001985198520012001年全国报告的年全国报告的STDSTD发病率发病率 1955-2003
15、年全国狂犬病发病率00.10.20.30.40.50.60.70.81955 1960 1965 1970 1975 1980 1985 1990 1995 2000发病率发病率(1/10万万)The Morbidity of Lupomania in China传染病流行病学基本原理和方法传染病流行病学基本原理和方法The basic principles and methods of infectious disease epidemiology(一)传染源(一)传染源Source of Infection定义定义 体内体内有病原体生长、繁殖并且能排出病原体的人和动物。有病原体生长、繁殖并
16、且能排出病原体的人和动物。分类分类 病人病人 casescases 病原病原携带者携带者 carrierscarriers 受受感染的动物感染的动物 animals animals 1、病人、病人 (cases)体内存在大量病原体体内存在大量病原体 In vivo existence massive pathogen 具有利于病原体排出的临床症状具有利于病原体排出的临床症状 Clinical symptoms are advantageous for the pathogen discharges 潜伏期潜伏期(Incubation periodIncubation period)F自病原体侵
17、入机体到最早临床症状出现这一段自病原体侵入机体到最早临床症状出现这一段时间时间FThe time interval between invasion by an infectious agent and appearance of the first signor symptom of the disease in question潜伏期的意义潜伏期的意义Significance of Incubation Period判断患者受感染时间判断患者受感染时间 To Determine The Infected Time 追踪传染源追踪传染源 Tracing Sources Of Infectio
18、n查明传播途径查明传播途径 To Identified The Route Of Transmission 确定接触者的留验、检疫和医学观察期限确定接触者的留验、检疫和医学观察期限 To Determine The Quarantine And Medical Observation Period 潜伏期的意义潜伏期的意义 Significance of Incubation Period确定免疫接种时间确定免疫接种时间 To Determine The Time Of Immunization 评价预防措施效果评价预防措施效果 Evaluation Of Effectiveness Of P
19、reventive Measures 潜伏期长短还可影响流行特征潜伏期长短还可影响流行特征 Can Affect The Epidemic Characteristics2、病原携带者(carrier)p没有任何临床症状而能排出病原体的人或动物没有任何临床症状而能排出病原体的人或动物A person or animal that harbors a specific infectious agent in the absence of discernible clinical disease and serves as a potential source of infection 3、受感染
20、的动物受感染的动物(infectious animal)自然疫源性疾病(natural focal disease)病原体在自然界中的动物间传播,在一定条件下病原体在自然界中的动物间传播,在一定条件下可以传给人所致的疾病。具有严格的地方性特点。可以传给人所致的疾病。具有严格的地方性特点。鹦鹉热、鼠疫、莱姆病、登革热鹦鹉热、鼠疫、莱姆病、登革热 流行性出血热、流行性出血热、西尼罗热西尼罗热人畜共患疾病:在脊椎动物和人之间自然传播的疾病和感染,即人和脊椎动物由共同的病原体引起的并在流行病学上有关联的疾病。Transmission of infectious agent from animal to
21、 human called ZOONOSES美洲狮美洲狮 传播西尼罗热的动物传播西尼罗热的动物Animals can transmit West Nile feverP病原体从传染源排出后,侵入新的易感宿主前,病原体从传染源排出后,侵入新的易感宿主前,在外环境中所经历的全部过程。在外环境中所经历的全部过程。(二)传播途径(二)传播途径 Route of TransmissionPThe whole process that the pathogens experienced in the outer environment when they passed from an infected i
22、ndividual or group to a previously uninfected individual or group.传染病传染病之之传播传播方式方式NAir-borne transmissionNWater-borne transmissionNFood-borne transmission NContact-transmitted diseasesNVector-borne diseasesNSoil-transmitted diseasesNNosocomial infectionNVertical transmissionC 经空气传播C 经水传播C 经食物传播C 接触传
23、播C 虫媒传播C 经土壤传播C 医源性传播C 垂直传播Modes of Infectious Disease Transmission1、空气传播传染病空气传播传染病(Air-borne diseases)传播途径易实现,易爆发流行传播途径易实现,易爆发流行 Transmission easy to comply,easy to outbreak冬春季高发冬春季高发 Mostly occurs in winter and spring 少年儿童多见少年儿童多见 Mostly occurs in Children未免疫预防人群周期性升高未免疫预防人群周期性升高 A cycle period in
24、 non-immunity population 受居住条件和人口密度的影响受居住条件和人口密度的影响 Overcrowded live conditions and high population density 2-1、饮用水污染饮用水污染(Drinking Water Pollution)病例分布与供水范围一致病例分布与供水范围一致 Distribution Of Cases Consistent With The Water Supply Coverage除哺乳婴儿外,其余人群均可发病除哺乳婴儿外,其余人群均可发病 Except To Lactated Infants,All Popu
25、lation Can Be 2-1、饮用水污染饮用水污染(Drinking Water Pollution)如经常被污染,可表现为慢性流行经过如经常被污染,可表现为慢性流行经过 If Often Contaminated,Can Be Expressed As Chronic Epidemic 如一次性严重污染,可出现爆发流行如一次性严重污染,可出现爆发流行 A Serious Pollution Can Cause An Outbreak 水源停用或净化后,爆发或流行可平息水源停用或净化后,爆发或流行可平息 Stop Drink Or Purified Water,Can Quell The
26、 Outbreak Or Epidemic 2-2、疫水接触疫水接触(Exposure to infected water)疫水接触史疫水接触史 History of exposure to infected water地区、季节与职业上的差别地区、季节与职业上的差别 There are regional,seasonal and occupational characteristics 多见于与疫水接触的人群多见于与疫水接触的人群 More common in people who contact with infected water大量易感人群与疫水接触可爆发大量易感人群与疫水接触可爆发
27、 A large number of susceptible who contact with infected water easy occur outbreaks 对疫水采取措施可控制发生对疫水采取措施可控制发生 Taken against measures can be controlled 3 3、经食物传播、经食物传播(Food-borne Diseases)吃污染食物者发病,不食者不发病吃污染食物者发病,不食者不发病 Involved Are Limited To Those Who Eat Contaminated Food 一次性大量污染,可形成爆发一次性大量污染,可形成爆发
28、A Large Number Of Contamination,The Outbreak Can Be Occur 停止供应该食物后,爆发即可平息停止供应该食物后,爆发即可平息 To Stop Supplying The Contaminated Food,The Outbreak Can Be Stop潜伏期较短潜伏期较短 The Incubation Period Is Shorter 1988年上海市甲型肝炎爆发和毛蚶年上海市甲型肝炎爆发和毛蚶 上海市上海市19881988年年1313月急性肝炎发病动态月急性肝炎发病动态 4 4、经接触传播、经接触传播Contact-transmitte
29、d diseases方式方式直接接触 Direct contact 没有外界因素参与下,传染源直接与易感者接触。没有外界因素参与下,传染源直接与易感者接触。间接接触 Indirect contact 易感者接触了被传染源的排出物或分泌物污染的用易感者接触了被传染源的排出物或分泌物污染的用品所造成的传播。品所造成的传播。5 5、经节肢动物传播、经节肢动物传播 (Vector-borne diseases)特征特征地区性地区性 Regional 西尼罗热西尼罗热职业性职业性 Occupational 森林脑炎森林脑炎季节性季节性 Seasonal 疟疾疟疾 青壮年多发青壮年多发 More Youn
30、g adults 地方性斑疹伤寒地方性斑疹伤寒媒介节肢动物媒介节肢动物埃及伊蚊埃及伊蚊蜱蜱白蛉白蛉库蚊库蚊疟疾、疟疾、丝虫病、丝虫病、乙脑、乙脑、登革热、登革热、黄热病、黄热病、西尼罗脑炎西尼罗脑炎等等新疆出血热、新疆出血热、蜱媒脑炎蜱媒脑炎、莱姆病莱姆病白蛉热、白蛉热、利夫特谷热利夫特谷热6、医源性传播医源性传播(Nosocomial infection)医疗、预防工作中,由于未严格地执行规章制医疗、预防工作中,由于未严格地执行规章制度和操作规程而造成的传播度和操作规程而造成的传播。Nosocomial infections(pronounced,nos-uh-KOH-mee-uhl),ar
31、e infections which are a result of treatment in a hospital or a healthcare service unit.7、围产期传播围产期传播(Vertical transmisssion)定义定义 在围产期病原体通过母体传给子代,也称垂直传播或母在围产期病原体通过母体传给子代,也称垂直传播或母婴传播婴传播。方式方式经胎盘传播经胎盘传播 By placenta 上行性感染上行性感染 By genital分娩时传播分娩时传播 By labour 人群作为一个整体对传染病的易感程度。人群作为一个整体对传染病的易感程度。The suscept
32、ibility degree of population,as a whole,to infectious diseases(三)人群易感性(三)人群易感性 Herd Susceptibility升高的因素升高的因素 (The Increase FactorsThe Increase Factors)新生儿增加新生儿增加 Increased Neonatal 易感人口迁入易感人口迁入 Susceptible Population Move In 免疫人口免疫力自然消退免疫人口免疫力自然消退 Mmuno-population Immunity To Natural Healing 免疫人口死亡免
33、疫人口死亡 Immuno-population Has Been Dead 降低的因素降低的因素 (Reduction FactorReduction Factor)计划免疫计划免疫 EPI 传染病流行传染病流行 Epidemics隐性感染隐性感染 Subclinical infection1、概念(concept)在一定条件下,传染源向其周围传播病原在一定条件下,传染源向其周围传播病原体所能波及的范围。体所能波及的范围。(四)疫源地(四)疫源地 Infectious focus The range that the sources of infection spread pathogens
34、around can reach to under certain conditions.2、形成条件 (the formation conditions)8传染源存在传染源存在 The source of infection exists 8 病原体能够继续传播病原体能够继续传播 Pathogens can continue to spread 3、消灭条件(eliminate conditions)Y传染源被移走或消除了携带状态传染源被移走或消除了携带状态 The source of infection has been removed or eliminate the carrier s
35、tateY进行了终末消毒进行了终末消毒 Carried out terminal disinfectionY经过最长潜伏期,易感者中没有新的感染发生经过最长潜伏期,易感者中没有新的感染发生 After the longest incubation period,no new infections occur among susceptible (五)影响流行过程的因素(五)影响流行过程的因素The factors that affect the epidemic process 1、自然因素自然因素(Natural factors)气候气候 (ClimateClimate)地理因素地理因素 (
36、GeographyGeography)媒介昆虫和宿主动物的特异性栖息习性媒介昆虫和宿主动物的特异性栖息习性 (Vector insects and hostVector insects and host)2、社会因素社会因素(Social factors)E全球旅游业的急剧发展全球旅游业的急剧发展 The rapid development of global travelThe rapid development of global travelE环境污染和破坏造成生态恶化环境污染和破坏造成生态恶化 Ecological deterioration caused by Ecological
37、deterioration caused by environmental pollution and environmental pollution and destructiondestruction 2、社会因素社会因素(Social factors)E抗生素和杀虫剂的滥用抗生素和杀虫剂的滥用 The abuse of antibiotics and pesticidesThe abuse of antibiotics and pesticides E城市化和人口爆炸城市化和人口爆炸 Urbanization and population explosionUrbanization an
38、d population explosionE战争、动乱、难民潮和饥荒战争、动乱、难民潮和饥荒 War,riots,refugee flows and famineWar,riots,refugee flows and famine传染病的预防和控制传染病的预防和控制Prevention and control of infectious diseases Immunization of people boosters frequently required 100%immunization is not necessary(herd immunity)Blocking vehicle-med
39、iated transmission water purification effective cooking prevention of food contamination with infectious agentsPublic Health Measures for Control of EpidemicsInvolves strategies which break the chain of transmission Quarantine limiting freedom of movement of individuals carrying infectious agents mi
40、nimum time required for a quarantine period is equal to longest period of communicability(transmissibility)of the disease Elimination of animal reservoirs immunization of animals that act as reservoirs of diseases such as bovine tuberculosis,brucellosis(highly effective when monitored properly)eradi
41、cation of animals that act as reservoirs of diseases such as tularemia,plague,Lyme disease(sometimes effective,difficult to monitor properly)Prevention,Intervention,Control,and Eradication of DiseasesControl of Infectious diseasesHUMAN1.Change behavior2.Health education3.VaccinationENVIRONMENT1.Habi
42、tat improvement2.Water(or soil)treatment3.Revise agriculture patternControl of Infectious diseasesRESERVOIRS1.Treatment2.Vaccination3.EradicationVECTORS1.Chemical control2.Non-chemical controlJ 加强传染病监测加强传染病监测 Communicable disease surveillance J 传染病报告传染病报告 Report infectious diseases 针对传染源的措施针对传染源的措施T
43、he control measures for the source of infection(1 1)病人)病人 Cases 早发现早发现 Early detection 早诊断早诊断 Early diagnosis 早报告早报告 Early reporting 早隔离早隔离 Early isolation 早治疗早治疗 Early treatment 病原携带者病原携带者 Carriers 措施措施 Measures 登记登记 Registration 管理管理 Management 随访随访 Follow up期限期限 Time limit 接触者接触者 Contacts 检疫检疫 Qu
44、arantine 留验留验(隔离观察隔离观察)Isolated observation 医学观察医学观察 Medical observation动物传染源动物传染源 Animal A彻底消灭彻底消灭 WipeA捕杀、焚烧或深埋捕杀、焚烧或深埋 Killing,burning or deepA隔离治疗隔离治疗 Isolation and treatmentA预防接种和检疫预防接种和检疫 Vaccination and quarantine 对传播途径的措施对传播途径的措施measures for route of transmission 消毒消毒 Disinfection 分类分类 预防性消毒预防性消毒 Preventive disinfection 疫源地消毒疫源地消毒Foci disinfection 随时消毒 Disinfection at any time 终末消毒 Terminal disinfection 分类分类 针对易感者的措施针对易感者的措施Measures for the susceptibleF免疫预防免疫预防 ImmunizationF药物预防药物预防 Drug prevention F个人防护个人防护 Personal Protection