【流行病学课件】疾病分布

1、Department of Epidemiology Public Health College of Harbin Medical University1Department of Epidemiology Public Health College of Harbin Medical UniversityWhat is Distribution of Disease When Where WhoINTRODUCTIONDepartment of Epidemiology Public Health College of Harbin Medical University3疾病的分布是指疾病

2、的人群现象疾病的分布是指疾病的人群现象 是描述疾病事件（发病、患病、死亡等）是描述疾病事件（发病、患病、死亡等） Time Time （时间）（时间） Place Place （空间）（空间） PersonPerson（人间）（人间） 在流行病学中简称在流行病学中简称“三间分布三间分布”Department of Epidemiology Public Health College of Harbin Medical University4ExampleYou have been asked to investigate an event in which 2,220 people were

3、exposed and 1,520 of them died. Your role as an epidemiologist is to ask questions about person, place and time.Department of Epidemiology Public Health College of Harbin Medical University5How do we ask questions?Surveys-of survivors-of other related personsExampleDepartment of Epidemiology Public

4、Health College of Harbin Medical University6Objectives第一节疾病频率测量指标第一节疾病频率测量指标第二节第二节 疾病流行强度疾病流行强度第三节第三节 疾病分布形式疾病分布形式Frequency of Disease Measurement Intensity of Epidemic Dimension distributions of diseaseDepartment of Epidemiology Public Health College of Harbin Medical University7Directions: This ch

5、apter describes the basic measures of disease frequency used in epidemiologic research Frequency of Disease Measurement 第一节第一节 疾病频率测量指标疾病频率测量指标Department of Epidemiology Public Health College of Harbin Medical University8发病频率测量指标发病频率测量指标患病频率测量指标患病频率测量指标死亡频率测量指标死亡频率测量指标预期寿命及相关指标预期寿命及相关指标Morbidity fre

6、quency measuresPrevalence related measuresMortality frequency measuresLife expectancy related measuresDepartment of Epidemiology Public Health College of Harbin Medical University9一、发病指标一、发病指标发病率（发病率（incidence）罹患率（罹患率（attack rate）续发率（续发率（secondary attack rate）Department of Epidemiology Public Health

7、 College of Harbin Medical University10发病率（发病率（incidence） 定义定义 在一定期间内，一定人在一定期间内，一定人群中某病新发生的病例出群中某病新发生的病例出现的频率。现的频率。 Definition the rate of new cases of a disease in a specified population over a defined period 发病率发病率= K K=100%,1000/千，或千，或10000/万万 一定期间内某人群中某病新病例数一定期间内某人群中某病新病例数同时期暴露人口数同时期暴露人口数 Depart

8、ment of Epidemiology Public Health College of Harbin Medical University11Incidence rateNumeratorNew (incident) cases appearing during a time period (usually one year)DenominatorAverage population during the time periodMidpoint population estimate Cases per 10X per year Example: 234 per 100,000 per y

9、earDepartment of Epidemiology Public Health College of Harbin Medical University12罹患率（罹患率（attack rate）定义定义 在某一局限范围，在某一局限范围，短时间内的发病率。短时间内的发病率。观察时间可以日、周、观察时间可以日、周、旬、月为单位。旬、月为单位。 Definition the proportion of a population affected by the disease during a prescribed, usually short, period of time. .Depar

10、tment of Epidemiology Public Health College of Harbin Medical University13Incidence rate and attack ratesv An outbreak of hepatitis A in Ajloon from March 1 to march 14 2000 had an attack rate of 25 per 1000 The yearly incidence rate of hepatitis A . in Ajloon is 238 per 100,000 per year How do you

11、compare these rates?Department of Epidemiology Public Health College of Harbin Medical University14Is their an outbreak?Incidence and attack rates compared 1. Adjust population to make rates comparable Divide 238 per 100,000 by 100 2.38 per 1000 per year 2. Adjust time period 2 weeks = 2/52 year 0.1

12、1 per 1000 per 2 weeks 南方南方Schistosomiasis is limited in some provinces in the southHIV infection in Yunnan ProvinceNasopharyngeal carcinoma in GuangdongEsophageal cancer in Henan Jiangsu Qidong Liver CancerHypertension north South Department of Epidemiology Public Health College of Harbin Medical U

13、niversity92 Fig18. Chinas cumulative reported HIV infection distribution by province (1985-2001) Department of Epidemiology Public Health College of Harbin Medical University93疾病的城乡分布疾病的城乡分布 The disease city and countryside distribution 城市城市 City人口多，密度大人口多，密度大 Population is many , density is big 交通拥

14、挤，人口流动性大交通拥挤，人口流动性大 Traffic congestion, population mobility较少经水传播传染病流行较少经水传播传染病流行 Less water-borne epidemics 虫媒传染病虫媒传染病 农村农村 Insect intermediary infectious disease 城市城市Insect intermediary infectious disease City某些地方病发病率某些地方病发病率The incidence of certain endemic diseases呼吸道传染病不易流行呼吸道传染病不易流行Respiratory

15、tract infectious disease not easy popular 疾病的城乡分布疾病的城乡分布 The disease city and countryside distribution Department of Epidemiology Public Health College of Harbin Medical University95 疾病的地区聚集性疾病的地区聚集性 （endemic clustering） 定义定义疾病频率高于周围地区的情况疾病频率高于周围地区的情况 Disease frequency is higher than the surrounding

16、 area Department of Epidemiology Public Health College of Harbin Medical University96 地方性疾病（简称地方病）地方性疾病（简称地方病） 定义定义指局限于某些特定地区内相对稳定并指局限于某些特定地区内相对稳定并经常发生的疾病。在我国地方病指与当地水土经常发生的疾病。在我国地方病指与当地水土因素、生物学因素有密切关系的疾病，其病因因素、生物学因素有密切关系的疾病，其病因存在于发病地区的水、土壤、粮食中存在于发病地区的水、土壤、粮食中 。 Present in a community at all times bu

17、t in relatively low frequency. Something that is endemic is typically restricted or peculiar to a locality or region. Department of Epidemiology Public Health College of Harbin Medical University97判断依据判断依据该地区的各类居民、任该地区的各类居民、任何民族的发病率均高何民族的发病率均高在其他地区居住的相似在其他地区居住的相似的人群中该病的发病频的人群中该病的发病频率均低，甚至不发病。率均低，甚至不

18、发病。incidence of the disease in any ethnic may increase in the residents in the area similar residents lived in other areas have the lower incidence, or even not occur the disease criteria of endemic diseasesDepartment of Epidemiology Public Health College of Harbin Medical University98criteria of en

19、demic diseaseswho immigrate the area over a period of time, its incidence approaches that in local population; the people emigrate the area, the incidence would reduce, or symptoms alleviate or self-healing.in addition, the local animals are also susceptible to the same disease迁入该地区的人经一段时间迁入该地区的人经一段

20、时间后，其发病率和当地居民一致后，其发病率和当地居民一致人群迁出该地区后，发病率下人群迁出该地区后，发病率下降或患病症状减轻或自愈降或患病症状减轻或自愈当地的易感动物也可发生同当地的易感动物也可发生同样的疾病样的疾病判断依据判断依据Department of Epidemiology Public Health College of Harbin Medical University99p移民流行病学移民流行病学 （migrant epidemiology）p 定义定义 对移民人群的疾病分布进行研究，以探对移民人群的疾病分布进行研究，以探讨病因。它是通过观察疾病在移民、移民移入国讨病因。它是通

21、过观察疾病在移民、移民移入国当地居民及原居地人群间的发病率、死亡率的差当地居民及原居地人群间的发病率、死亡率的差异，从其差异中探讨病因线索，区分遗传因素或异，从其差异中探讨病因线索，区分遗传因素或环境因素作用的大小。环境因素作用的大小。 Department of Epidemiology Public Health College of Harbin Medical University100若环境因素是主要因素若环境因素是主要因素 移民移民原居住地人群原居住地人群发病率或死亡率发病率或死亡率 移民移民移居地当地居民移居地当地居民若遗传因素是主要因素若遗传因素是主要因素 移民移民原居住地人群

22、原居住地人群发病率或死亡率发病率或死亡率 移民移民移居地当地居民移居地当地居民Department of Epidemiology Public Health College of Harbin Medical University101Local residents in Japan, the United States white and third generation, second-generation Japanese immigrants age specific death rate of gastric cancer Fig19Department of Epidemiology Public Health College of Harbin Medical University102分析结果分析结果注意注意 移民移居他地的原因及移民本身的人口学移民移居他地的原因及移民本身的人口学特征。特征。 如：年龄、职业、文化水平、社会经济状如：年龄、职业、文化水平、社会经济状况、种族和其他人口学因素及其工作条件、生况、种族和其他人口学因素及其工作条件、生活环境的变化是否和非移民相同。活环境的变化是否和非移民相同。Department of Epidemiology Public Health College of Harbin Medical