BIOL 4105 Chapter : 6 12 12
Document Summary
6/12/12: vector: tsetste fly (glossina spp, thousands of metacyclic tryp in saliva of one bite. African trypanosome life cycle stages: epimastigote in vector only, metacyclic trypomastigote infective stage of vector, trypomastigote in vertebrate host. Cdc trypanosoma life cycle image* (when you get bitten by a tsetse fly then the parasite is transmitted and the metacyclic trypomastigote enters the bite wound. Once they completed and got into the bloodstream, they multiply by binary fission. Eventually they make their way into the brain. Tsetse ingests trypomastigotes, then in fly transform into epimastigotes. After transformation , parasite move out and chancre heals: heals completely without scarring (2-3 wks) No evidence that she was bitten: stage 1: parasitemia waves ; rise and fall in numbers of parasites during replication (immune system killing them off, but they come back) nonspecific symptoms, high fevers, rash, lymphadenopathy. Winterbottom"s sign : malaise (don"t feel good) and lethargy, there is nothing specific in those clinical signs.
