絲蟲是由節(jié)肢動(dòng)物傳播的一類線蟲,寄生于人體的已知有8種,其中班氏絲蟲和馬來絲蟲引起的淋巴絲蟲病(Filariasis)及由盤尾絲蟲所致的"河盲癥"對(duì)人類危害最嚴(yán)重。我國只有前兩種:班氏吳策線蟲(Wuchereria bancrofti)和馬來布魯線蟲(Brugia malayi)。
一、形態(tài)
成蟲
乳白色,細(xì)長如絲線,體長不到1cm;雄蟲尾端卷曲半到3圈,具交合刺。雌蟲大于雄蟲,尾端直。
班氏與馬來微絲蚴形態(tài)鑒別
項(xiàng)目 |
班氏微絲蚴 |
馬來微絲蚴 |
體態(tài) 頭隙 尾核 |
柔和,彎曲 較大較短,長短于寬;清晰可數(shù) 無 |
硬直,大彎上有小彎 較長,長大于寬;不易數(shù)清 有2個(gè),前后排列 |
Microfilaria of Wuchereria bancrofti
stained with haematoxylin. Sheath is visible at the posterior end. ×400. Enlarged by 5.4.
Microfilaria of Wuchereria bancrofti
stained with Giemsa. Sheath is not stained, but appears as an empty space. ×400. Enlarged by 5.4.
Microfilaria of Brugia malayi
stained with Giemsa. The sheath takes a dark pink stain. ×400. Enlarged by 5.4.
Microfilaria of Brugia malayi
showing the terminal nuclei and the darkly staining sheath. Giemsa. ×800. Enlarged by 5.4.
Microfilaria of Brugia malayi
showing the terminal nuclei. Acridine orange. ×800. Enlarged by 5.4.
感染期幼蟲又叫絲狀蚴,寄生于蚊體內(nèi),為感染階段。