A woman who impos food from Mexico and spends several months per year in rural Mexico had to have a compound leg fracture pinned and set in Mexico and has returned 3 days later. She now has signs of acute appendicitis and is taken to surgery in Houston. When her appendix is removed, it is found to contain a light-colored, 20.5-cm long roundworm and bile-stained knobby eggs consistent with Ascaris. How did she acquire this infection?
High-Yield Explanation
Infection in humans is acquired through ingestion of the embryonated eggs from contaminated soil . Embryonated Ascaris eggs released in feces may contaminate food or water, which is then consumed. Ascaris does not attach to the intestine but maintains its position by mobility. The worm may become hypermotile (e.g., during febrile periods, anesthetic use, or antibiotic use) and may migrate into the appendix or bile duct.