医院医科医学系统教学培训课程：虱蚤

关于医学我们有话说之虱蚤虱louse虱是一种体外永久性寄生虫。寄生于人体的虱有两种，人虱和耻阴虱。人虱又分为人体虱和人头虱两个亚种。人虱体狭长，背腹扁平。♀可达4.4mm，♂稍小。雄虱末端近似“V”形，雌虱末端呈“W”形。头呈菱形，有触角一对。胸部三节愈合有足三对，各足胫节内侧的指状胫突与末端的爪相对，形成强有力的抓握器。头虱较体虱略小，颜色稍深。耻阴虱体形短而宽，呈蟹状。一、形态二、生活史与生态习性5—9天蜕皮3次1、寄生部位人头虱：头发，产卵于发根，以耳后较多。人体虱：贴身衣服的缝、褶，产卵于衣裤的织物纤维上。耻阴虱：阴毛、肛毛。其它部位以睫毛较多见，产卵于毛的基部。2、与传病有关的习性吸血特性；对温度，湿度均敏感；爬行速度快。卵——————若虫——————成虫卵椭圆形，白色，俗称虮子。卵粘附在毛发或纤维上，其游离端有盖，上有气孔和小室。[LastModified:11/20/200015:59:02][Pediculushumanuscapitis]HeadLice-nymphhatchingthroughtheoperculumofanegg.Theegghatchesreleasinganymph.Thenitshellthenbecomesamorevisibledullyellowandremainsattachedtothehairshaft.Thenymphlookslikeanadultheadlouse,butisaboutthesizeofapinhead.Nymphsmatureafterthreemoltsandbecomeadultsabout7daysafterhatching.[LastModified:11/20/200015:59:02][Pediculushumanuscapitis]HeadLice-nymphhatchingthroughtheoperculumofanegg.Theegghatchesreleasinganymph.Thenitshellthenbecomesamorevisibledullyellowandremainsattachedtothehairshaft.Thenymphlookslikeanadultheadlouse,butisaboutthesizeofapinhead.Nymphsmatureafterthreemoltsandbecomeadultsabout7daysafterhatching.HeadLice-nymphhatchingthroughtheoperculumofanegg.Theegghatchesreleasinganymph.Thenitshellthenbecomesamorevisibledullyellowandremainsattachedtothehairshaft.Thenymphlookslikeanadultheadlouse,butisaboutthesizeofapinhead.Nymphsmatureafterthreemoltsandbecomeadultsabout7daysafterhatching.三、传播疾病•流行性斑疹伤寒病原为普氏立克次氏体•回归热病原为俄拜氏疏螺旋体四、防治•加强卫生宣教，注意个人卫生，做到“四勤”•灭虱措施：烫、冻、毒（20%百部酒精浸液或0.01%二氯苯醚菊酯）五、流行GeographicDistribution:Headliceinfestationisverycommonandisdistributedworldwide;6to12millionpeoplemaybeaffectedyearly.Preschoolandelementary-agechildren,3to10yearsofageareinfestedmostoften.Femalesareinfestedmoreoftenthanmales,probablyduetomorefrequentheadtoheadcontact.IntheUnitedStates,African-Americansarerarelyinfestedwithheadlice.ThisisbelievedtobeduetotheAmericanlouse’spreferencefortheshapeandwidthofthehairshaftofotherraces.蚤Flea•俗称跳蚤、蛤蚤。寄生于恒温动物体表。•一、形态左右侧扁。头呈三角形，触角一对，藏于触角窝内。全身的鬃、毛、栉一律向后长。足强壮发达，善跳。二、生活史蚤生活史为全变态，包括卵、幼虫、蛹和成虫4个时期茧内的蛹羽化时需要外界的刺激。如空气的震动，动物走近的扰动和接触压力以及温度的升高等，都可诱使成虫破茧而出。三、与疾病的关系蚤对人的危害除了骚扰吸血及寄生外，还可传播多种疾病：1、鼠疫鼠疫杆菌2、鼠型斑疹伤寒莫氏立克次氏体3、绦虫病微小膜壳绦虫缩小膜壳绦虫犬膜壳绦虫四、防制•1、10%---30%百部+酒制成百部酊，杀灭成虫、若虫•2、灭虱香波