MCB 2004C Lecture Notes - Lecture 30: Giardia Lamblia, Leishmania Infantum, Plasmodium Malariae
Document Summary
Parasites: organisms that live on or in other living organisms, at whose expense they gain some advantage. Definitive host harbors adult or sexual stage. Intermediate host larval or asexual stage. Cysts excreted, viable for up to 3 months. Sudden onset with foul smelling, watery diarrhea. Irritation of mucosa, increased mucus secretion, epigastric pain, increased fat and mucus, no blood. Fecal-oral ingestion of cysts in food, water. Microscopy of trophozoites or cysts in stained fecal specimens. Symptoms: dysentery, fever, chills, bloody or mucoid diarrhea or constipation, colitis. Vaginitis profuse, thin, foamy, malodorous, greenish-yellow discharge. Etiology: l. major, l. infantum, l. braziliensis. Reservoir: zoonosis humans, dogs, wild animals. 12 million infected, 2 million new cases/year. Visceral (aka kala-azar) fever, enlarged liver/spleen, lymphadenopathy, anemia, leukopenia, emaciation and weakness. Sporozoite: the infectious form of the malaria parasite, which is injected into people by mosquitoes. Merozoite: the form of the malaria parasite that invades red blood cells.
