Warren K S
Rev Infect Dis. 1982 Jul-Aug;4(4):771-5. doi: 10.1093/4.4.771.
Schistosomes are helminths of the class Trematoda that alternate generations, with a sexual phase in definitive mammalian hosts and an asexual phase in intermediate snail hosts. In humans, these blood flukes reside in the mesenteric and vesical venules. They have a life span of many years and daily produce large numbers of eggs, which must traverse the gut and bladder tissues on their way to the lumens of the excretory organs. Many of the eggs remain in the host tissues, inducing immunologically mediated granulomatous inflammation and fibrosis. Heavy worm burdens may produce hepatosplenic disease in schistosomiasis mansoni and japonica and urinary tract disease in schistosomiasis haematobia. Since both the schistosomes and the eggs utilize host metabolites, and since the host responses to the parasite are affected by its nutritional status, malnutrition may strongly affect both the parasite and the complex host-parasite relationship.
血吸虫是吸虫纲的蠕虫，具有世代交替现象，在终末哺乳动物宿主中进行有性生殖阶段，在中间螺宿主中进行无性生殖阶段。在人类中，这些血吸虫寄居于肠系膜和膀胱小静脉中。它们的寿命长达数年，每天会产生大量虫卵，这些虫卵在通向排泄器官管腔的途中必须穿过肠道和膀胱组织。许多虫卵会留在宿主组织中，引发免疫介导的肉芽肿性炎症和纤维化。严重的虫负荷可在曼氏血吸虫病和日本血吸虫病中导致肝脾疾病，在埃及血吸虫病中导致泌尿系统疾病。由于血吸虫和虫卵都利用宿主代谢产物，并且宿主对寄生虫的反应受其营养状况影响，营养不良可能会强烈影响寄生虫以及复杂的宿主 - 寄生虫关系。
