蛔虫鞭虫钩虫课件

成虫
（小肠） 录像
卵
随粪入土
感染期卵
潮湿、荫蔽、O2充足 21-30。C
经口误食、孵出幼虫、体内移行
蛔虫幼虫的体内移行：
侵入肠粘膜的小V、小L
门静脉 肝
右心 肺
肺泡（蜕皮2次） 支气管
气管
咽
食管 胃
小肠（蜕皮1次）
生活史的特点：
ቤተ መጻሕፍቲ ባይዱ
1. Site of inhabitation: small intestine
关于蛲虫，下列哪项是错误的：
1.生活史简单 2.感染率儿童高于成人，城市高于农村
3.生活史属间接型 √
4.带虫者和病人是唯一的传染源 5.感染方式主要是人群中的间接接触和肛门 －手－口直接感染
P162
Ascaris Lumbricoides
Ascaris Lumbricoides
Ascaris lumbricoides , common saying “round worm of man”, is the largest of the intestinal nematodes parasitizing humans. It is the most common worm found in human. It is worldwide in distribution and most prevalent through out the tropics, subtropics and more prevalent in the countryside than in the city
There are two phases in ascariasis: 1. The blood-lung migration phase of the larvae: During the migration through the lungs, the larvae may cause a pneumonia. The symptoms of the pneumonia are low fever, cough, blood-tinged sputum, asthma. Large numbers of worms may give rise to allergic symptoms. Eosionophilia is generally present. These clinical manifestation is also called Loeffler’s syndrome.
寄生虫病的传播途径包括污染或含有 寄生虫的感染期的
土壤 √
水
√
食物 √
节肢动物传播媒介 √
寄生虫感染阶段是指寄生虫的：
感染人体阶段 √ 感染保虫宿主阶段 感染中间宿主阶段 感染中间宿主阶段 感染昆虫媒介阶段
人体寄生虫病的传染源包括：
仅有病人和带虫者 医学节肢动物 所有野生动物 病人、带虫者、感染的动物 √
2. The intestinal phase of the adults. The presence of a few adult worms in the lumen of the small intestine usually produces no symptoms, but may give rise to vague abdominal pains or intermittent colic, especially in children. A heavy worm burden can result in malnutrition. More serious manifestations have been observed. Wandering adults may block the appendical lumen or the common bile duct and even perforate the intestinal wall. Thus complications of ascariasis, such as intestinal obstruction, appendicitis, biliary ascariasis, perforation of the intestine, cholecystitis, pancreatitis and peritonitis, etc., may occur, in which biliary ascariasis is the most common complication.
2. Infetive stage: embryonated eggs
3. Route of infection: by mouth
4. No intermediate and reservoir hosts
5. Life span of the adult: about 1 year
III. Pathogenesis
四、诊断（diagnosis)
直接涂片法
录像
改良加藤法
五、流行与防治
(Endemity and Prevention)
World wide distribution, very common in China, especially in the countryside. Factors favoring the spread of the transmission: 1. Simple life cycle. 2. Enormous egg production ( 240,000 eggs/ day/ female ). 3. These eggs are highly resistant to ordinary disinfectants (due to the ascroside). The eggs may remain viable for several years. 4. Social customs and living habits. 5. Disposal of feces is unsuitable.
录像
致病（pathogenesis)
1、幼虫致病
蛔虫性哮喘
2、成虫致病
掠夺营养
引起变态反应 并发症
哮喘,荨麻疹
录像
并发症
(国内报告 8468例)
胆道蛔虫症 4556例(53.8%) 蛔虫性肠梗阻 2337例(27.6%) 蛔虫性阑尾炎 143例 蛔虫性胰腺炎 17例 蛔虫性哮喘 1352例 蛔虫性肝脓肿 33例
似蚓蛔线虫（蛔虫）
Ascaris lumbricoides
一、形态
成 虫
15~31cm ♂
活体 活体
20~35cm
♀
Adult worm of A. lumbricoides
蛔 虫
唇 瓣
扫 描 电 镜 图
虫卵
蛋白质膜
受
卵壳
未
精
卵细胞
受
卵
新月形间隙
精 卵
卵黄颗粒
脱蛋白质 膜受精卵
录像
二 生 活 史