Schistosoma japonicum: migration of adult worm pairs within the mesenteric veins of mice.
Mice infected with a single worm pair of a Japanese, a Philippine and a Formosan strain of Schistosoma japonicum were examined to determine the frequency of movement of worms within the mesenteric veins eight to 76 weeks after infection. By the 18th week after infection, one or more gross focal lesions developed in the gut, and 47 to 89% of eggs in the gut were concentrated in these lesions. In spite of this predominantly focal oviposition, oograms revealed first-stage eggs scattered throughout the gut, indicating frequent movement of the worms along the length of the intestine. Multiple gross lesions, often far from each other, were seen in half the mice. Our findings indicate that worms pairs move frequently, but that they are attracted to existing gross lesions, probably by substances released into the mesenteric blood from eggs or the surrounding inflammatory exudate.
D000818:Animals; D005260:Female; D007411:Intestinal Diseases, Parasitic / Q000469:parasitology*; D008642:Mesenteric Veins / Q000469:parasitology*; D051379:Mice; D009068:Movement; D010058:Oviposition; D012549:Schistosoma japonicum / Q000502:physiology*; D012552:Schistosomiasis / Q000469:parasitology*