埃博拉病毒病学习资料.pptx

Ebola Virus Disease(EVD)Wdx,2014.10About Ebola Virus Diseaseopreviously known as Ebola hemorrhagic fever,o a rare and deadly disease caused by infection with one of the Ebola virus strains.oonly caused disease in humans and nonhuman primates(monkeys,gorillas（大猩猩）,and chimpanzees（黑猩猩）).othe family Filoviridae,genus Ebolavirus.（丝状病毒科,埃博拉病毒属）o There are five identified Ebola virus species,four of which are known to cause disease in humans:Ebola virus(Zaire ebolavirus);Sudan virus(Sudan ebolavirus);Ta Forest virus(Ta Forest ebolavirus,formerly Cte dIvoire ebolavirus);and Bundibugyo（本迪布焦区，中非）virus(Bundibugyo ebolavirus).The fifth,Reston（雷斯顿，美国）virus(Reston ebolavirus),has caused disease in nonhuman primates,but not in humans.ofirst discovered in 1976 near the Ebola River in what is now the Democratic Republic of the Congo.Since then,outbreaks have appeared sporadically in Africa.oThe natural reservoir host of Ebola virus remains unknown.However,on the basis of evidence and the nature of similar viruses,researchers believe that the virus is animal-borne and that bats are the most likely reservoir.Four of the five virus strains occur in an animal host native to Africa.扎伊尔埃博拉病毒扎伊尔埃博拉病毒o扎伊尔埃博拉病毒有高达扎伊尔埃博拉病毒有高达90%的致死率，在流行地区死亡率的致死率，在流行地区死亡率1976年为年为88%、1977年为年为100%、1994年为年为59%、1995年为年为81%、1996年为年为73%、2001年至年至2002年为年为80%，2003年则年则是是90%，2007年平均为年平均为83%。o1976年年8月月26日首次于扎伊尔北边城镇爆发，首位个案纪录为日首次于扎伊尔北边城镇爆发，首位个案纪录为44岁岁教师教师Mabalo Lokela，当时他的高烧被诊断为疑似疟疾感染，并且，当时他的高烧被诊断为疑似疟疾感染，并且接受奎宁注射治疗，这位病人每日回医院就诊观察，一周后却恶化为接受奎宁注射治疗，这位病人每日回医院就诊观察，一周后却恶化为无法控制的呕吐，带血腹泻、头痛、晕眩伴随呼吸困难，并开始自口、无法控制的呕吐，带血腹泻、头痛、晕眩伴随呼吸困难，并开始自口、鼻、直肠等多处开始出血，于鼻、直肠等多处开始出血，于9月月18日过世，病程仅约日过世，病程仅约2周。周。o不久之后，更多病患带着相似的症状就医，包括发烧、头痛、肌肉痛、不久之后，更多病患带着相似的症状就医，包括发烧、头痛、肌肉痛、关节痛、疲倦、恶心、晕眩等。常发展成带血腹泻、严重呕吐和多发关节痛、疲倦、恶心、晕眩等。常发展成带血腹泻、严重呕吐和多发性出血，初期传染可能肇因于重复使用用过却未消毒之针筒，后续传性出血，初期传染可能肇因于重复使用用过却未消毒之针筒，后续传染主要则是照顾病患时，在没有适当安全措施的情况下受到病毒侵袭染主要则是照顾病患时，在没有适当安全措施的情况下受到病毒侵袭或传统埋葬前置作业的清洗过程。或传统埋葬前置作业的清洗过程。苏丹埃博拉病毒苏丹埃博拉病毒o苏丹埃博拉病毒在苏丹埃博拉病毒在1976年首次在苏丹棉花厂工人身上被发现。年首次在苏丹棉花厂工人身上被发现。研究人员指出，这名工人应该是在工厂中或附近接触到到带原研究人员指出，这名工人应该是在工厂中或附近接触到到带原生物宿主，但在检测过工厂附近的动物及昆虫后仍一无所获，生物宿主，但在检测过工厂附近的动物及昆虫后仍一无所获，带原宿主至今仍是未知。带原宿主至今仍是未知。o第二个病例是一位住在苏丹的夜店负责人，当地医院用尽所有第二个病例是一位住在苏丹的夜店负责人，当地医院用尽所有的方法治疗他都没有效果，最后还是宣告不治。医护人员在治的方法治疗他都没有效果，最后还是宣告不治。医护人员在治疗时并没有适当的防护措施，导致病毒传遍医院发生大爆发。疗时并没有适当的防护措施，导致病毒传遍医院发生大爆发。o2004年年5月，苏丹月，苏丹Yambio县回报县回报20个病例，并有五人死亡。个病例，并有五人死亡。疾病管制局在几天后确认这些病例为苏丹埃博拉，邻近国家例疾病管制局在几天后确认这些病例为苏丹埃博拉，邻近国家例如乌干达、刚果皆增加边界的守卫，以控制疫情。如乌干达、刚果皆增加边界的守卫，以控制疫情。1976年苏年苏丹埃博拉的平均死亡率为丹埃博拉的平均死亡率为53%，1979年为年为68%，2000年年至至2001年间为年间为53%，平均死亡率为，平均死亡率为53.76%。塔伊森林埃博拉病毒o首先在科特迪瓦的塔伊国家公园中被发现。在首先在科特迪瓦的塔伊国家公园中被发现。在1994年年11月月1日，日，二只黑猩猩尸体在森林里被发现。检验人员发现在心脏中的血液二只黑猩猩尸体在森林里被发现。检验人员发现在心脏中的血液是棕色的且已液化（通常尸体中的血液在死亡十几小时之后就应是棕色的且已液化（通常尸体中的血液在死亡十几小时之后就应该完全凝固），内脏外观并没有明显痕迹，肺中充满血液。从黑该完全凝固），内脏外观并没有明显痕迹，肺中充满血液。从黑猩猩身上采取到的组织显示，此病毒与苏丹埃博拉及猩猩身上采取到的组织显示，此病毒与苏丹埃博拉及1976年爆发年爆发的扎伊尔埃博拉十分相似。的扎伊尔埃博拉十分相似。1994年后，更多死亡的黑猩猩被发年后，更多死亡的黑猩猩被发现，科学家用许多方法对病毒进行检测。现，科学家用许多方法对病毒进行检测。o感染的来源被认为是一只被黑猩猩捕食且带有病毒的疣猴。感染的来源被认为是一只被黑猩猩捕食且带有病毒的疣猴。o执行尸体检验的其中一位科学家感染了病毒。她出现了类似登革执行尸体检验的其中一位科学家感染了病毒。她出现了类似登革热的症状并在一星期后被送到瑞士治疗。两个星期后出院，在感热的症状并在一星期后被送到瑞士治疗。两个星期后出院，在感染病毒之后的第六个星期完全康复。染病毒之后的第六个星期完全康复。本迪布焦亚埃博拉病毒本迪布焦亚埃博拉病毒o病死率为在33%左右（66/206），曾出现在刚果民主共和国和乌干达 o2007年9月，乌干达西部本迪布焦山区一个偏僻村庄的部分村民突然病倒，出现头痛、发烧、呕吐、腹泻及出血的症状，随后死去。亲属们在埋葬这些死者前清洗了尸体，病毒借此迅速传播开来。雷斯顿埃博拉病毒雷斯顿埃博拉病毒o1989年年11月首次在一群由菲律宾进口至美国维珍月首次在一群由菲律宾进口至美国维珍尼亚州雷斯顿的食蟹猴尼亚州雷斯顿的食蟹猴(Macaca fascicularis)身上发现。此一病毒对猴子有很高的致死率，但对身上发现。此一病毒对猴子有很高的致死率，但对人类并没有致命性。人类并没有致命性。o1990年年2月，雷斯顿埃博拉病毒再次在雷斯顿、月，雷斯顿埃博拉病毒再次在雷斯顿、德州及菲律宾爆发。德州及菲律宾爆发。1992年及年及1996年，更多病年，更多病例在意大利托斯卡纳和德州发现。所有感染的猴只例在意大利托斯卡纳和德州发现。所有感染的猴只出现与猿猴出血热类似的症状。在这两次爆发中，出现与猿猴出血热类似的症状。在这两次爆发中，没有任何人类受到感染。没有任何人类受到感染。埃博拉出血热 埃博拉病毒对热有中度抵抗力在室温及4存放1个月后，感染性无明显变化60灭活病毒需要1小时 埃博拉病毒对紫外线、射线、甲醛、次氯酸、酚类等消毒剂和脂溶剂敏感Symptoms and Laboratory findings oSymptoms of Ebola includeFever(greater than 38.6C or 101.5F)Severe headache Muscle pain Weakness Diarrhea Vomiting Abdominal(stomach)pain Unexplained hemorrhage(bleeding or bruising)oFirst symptoms are the sudden onset of fever，fatigue,muscle pain,headache and sore throat.This is followed by vomiting,diarrhoea,rash,symptoms of impaired kidney and liver function,and in some cases,both internal and external bleeding(e.g.oozing（渗出）from the gums,blood in the stools).oSymptoms may appear anywhere from 2 to 21 days after exposure to Ebola,but the average is 8 to 10 days.oLaboratory findings include low white blood cell and platelet counts and elevated liver enzymes 临床表现急性起病，高热、畏寒、头痛、肌痛、恶心、结膜充血及相对缓脉。2-3天后可有呕吐、腹痛、腹泻、血便等表现，半数患者有咽痛及咳嗽。病人最显著的表现为低血压、休克和面部水肿。病程4-5天，可出现神志的改变，病程5-7日可出现麻疹样皮疹第10病日为出血高峰，广东省疾病预防控制中心发热严重头痛肌肉疼痛极度疲劳结膜充血0123456789 days皮疹腹泻、呕吐case fatality rate（CFR）25-90%临 床 表 现出血嗝逆嗜睡、谵妄、昏迷严重咽喉疼痛胸腹疼痛TransmissionoHumans are not infectious until they develop symptoms.oWhen an infection does occur in humans,the virus can be spread in several ways to others.Ebola is spread through direct contact(through broken skin or mucous membranes in,for example,the eyes,nose,or mouth)withblood or body fluids(including but not limited to urine,saliva,sweat,feces,vomit,breast milk,and semen)of a person who is sick with Ebola objects(like needles and syringes)that have been contaminated with the virus infected animals oEbola is not spread through the air or by water,or in general,by food.However,in Africa,Ebola may be spread as a result of handling bushmeat(wild animals hunted for food,丛林肉)and contact with infected bats.There is no evidence that mosquitos or other insects can transmit Ebola virus.Only mammals(for example,humans,bats,monkeys,and apes)have shown the ability to become infected with and spread Ebola virus.PreventionThe virus can enter the body through broken skin or unprotected mucous membranes in,for example,the eyes,nose,or mouthoPractice careful hygiene.For example,wash your hands with soap and water or an alcohol-based hand sanitizer and avoid contact with blood and body fluids.oDo not handle items that may have come in contact with an infected persons blood or body fluids(such as clothes,bedding,needles,and medical equipment).oAvoid funeral or burial rituals(葬礼仪式）that require handling the body of someone who has died from Ebola.oAvoid contact with bats and nonhuman primates(灵长目动物)or blood,fluids,and raw meat prepared from these animals.Preventionoexposed to people with Ebola should wear protective clothing,including masks,gloves,gowns（长袍）,and eye protection.oPractice proper infection control and sterilization measures.oIsolate patients with Ebola from other patients.oAvoid direct contact with the bodies of people who have died from Ebola.oNotify health officials if you have had direct contact with the blood or body fluids,such as but not limited to,feces,saliva,urine,vomit,and semen of a person who is sick with Ebola.THE CAP FORMS PART OF A PROTECTIVE HOOD COVERING THE HEAD AND NECKDiagnosisoDiagnosing Ebola in an person who has been infected for only a few days is difficult,because the early symptoms,such as fever,are nonspecific to Ebola infection and are seen often in patients with more commonly occurring diseases,such as malaria and typhoid fever.oif a person has the early symptoms of Ebola and has had contact with the blood or body fluids of a person sick with Ebola,contact with objects that have been contaminated with the blood or body fluids of a person sick with Ebola,contact with infected animals,o Samples from the patient can then be collected and tested to confirm infection.Case Definition for Ebola Virus Disease(EVD)oPerson Under Investigation(PUI)A person who has both consistent symptoms and risk factors as follows:oClinical criteria,which includes fever of greater than 38.6 degrees Celsius or 101.5 degrees Fahrenheit,and additional symptoms such as severe headache,muscle pain,vomiting,diarrhea,abdominal pain,or unexplained hemorrhage;AND oepidemiologic risk factors within the past 21 days before the onset of symptoms,such as contact with blood or other body fluids or human remains of a patient known to have or suspected to have EVD;residence inor travel toan area where EVD transmission is active*;or direct handling of bats or non-human primates from disease-endemic areas.oProbable CaseA PUI whose epidemiologic risk factors include high or low risk exposure(s)oConfirmed CaseA case with laboratory-confirmed diagnostic evidence of Ebola virus infectionExposure Risk LevelsoHigh risk exposuresA high risk exposure includes any of the following:oPercutaneous(e.g.,needle stick)or mucous membrane exposure to blood or body fluids of EVD patient oDirect skin contact with,or exposure to blood or body fluids of,an EVD patient without appropriate personal protective equipment(PPE)oProcessing blood or body fluids of a confirmed EVD patient without appropriate PPE or standard biosafety precautions oDirect contact with a dead body without appropriate PPE in a country where an EVD outbreak is occurring*oLow risk（some risk）exposuresA low risk exposure includes any of the followingoHousehold contact with an EVD patient oOther close contact with EVD patients in health care facilities or community settings.Close contact is defined as being within approximately 3 feet(1 meter)of an EVD patient or within the patients room or care area for a prolonged period of time(e.g.,health care personnel,household members)while not wearing recommended personal protective equipment(i.e.,standard,droplet,and contact precautions)having direct brief contact(e.g.,shaking hands)with an EVD patient while not wearing recommended personal protective equipment.oBrief interactions,such as walking by a person or moving through a hospital,do not constitute close contactoNo known exposureHaving been in a country in which an EVD outbreak occurred within the past 21 days and having had no high or low risk exposuresTreatmentoNo FDA-approved vaccine or medicine(e.g.,antiviral drug)is available for Ebola.oSymptoms of Ebola are treated as they appear.The following basic interventions,when used early,can significantly improve the chances of survival:Providing intravenous fluids(IV)and balancing electrolytes(body salts)Maintaining oxygen status and blood pressure Treating other infections if they occuroExperimental vaccines and treatments for Ebola are under development,but they have not yet been fully tested for safety or effectiveness.oRecovery from Ebola depends on good supportive care and the patients immune response.People who recover from Ebola infection develop antibodies that last for at least 10 years,possibly longer.It isnt known if people who recover are immune for life or if they can become infected with a different species of Ebola.oSome people who have recovered from Ebola have developed long-term complications,such as joint and vision problems.