GMED1000 Lecture Notes - Lecture 10: Trichinella, Diarrhea, Anemia
Document Summary
Platyhelminths: flat worms, e. g. tapeworm or liver fluke. Establishes in bile duct and feeds on liver. Produces large number of eggs, passed into faeces and gets into water system. Eggs eaten by water snails and larvae released. Causes fascioliasis: fever, tiredness, pain around liver, appetite loss. Larvae can develop in a wide range of tissues, inc. muscle. First symptoms: abdominal pain and diarrhoea as larvae invade intestinal wall. Secondary symptoms: muscle pain and fever as larvae invade and encyst in muscle. 1500 larvae before adult worm expelled from immune system. Insect bites human - sporozoite enters and reproduces in liver over several days - release merozoites into blood - infect red blood cells and bursts them to release more metrozoites. Lysis (bursting) of red blood cells cause fever, chills, nausea and headaches. Metrozoites produce trophozoites which can be taken up by mosquitos.