医院医科医学系统教学培训课程：虱蚤

1、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59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

2、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。 Last Modified: 11/20/2000 15:59:02 Pediculus humanus capitis Head Lice -nymph hatching through the operculum of an egg.The egg hatches releasing a nymph. The nit shell then becomes a more visible dull yellow and remains attached t

3、o the hair shaft. The nymph looks like an adult head louse, but is about the size of a pinhead. Nymphs mature after three molts and become adults about 7 days after hatching. Last Modified: 11/20/2000 15:59:02 Pediculus humanus capitis Head Lice -nymph hatching through the operculum of an egg.The eg

4、g hatches releasing a nymph. The nit shell then becomes a more visible dull yellow and remains attached to the hair shaft. The nymph looks like an adult head louse, but is about the size of a pinhead. Nymphs mature after three molts and become adults about 7 days after hatching.Head Lice -nymph hatc

5、hing through the operculum of an egg.The egg hatches releasing a nymph. The nit shell then becomes a more visible dull yellow and remains attached to the hair shaft. The nymph looks like an adult head louse, but is about the size of a pinhead. Nymphs mature after three molts and become adults about

6、7 days after hatching.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Geographic Distribution:Head lice infestation is very common and is distributed worldwide; 6 to 12 million people may be affected yearly. Preschool and elementary-age children, 3 to

7、 10 years of age are infested most often. Females are infested more often than males, probably due to more frequent head to head contact. In the United States, African-Americans are rarely infested with head lice. This is believed to be due to the American louses preference for the shape and width of the hair shaft of other races.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