Life cycle of Trypanosoma cruzi. Life cycle of Trypanosoma cruzi. An infected triatome vector or “kissing bug” takes a blood meal from a mammalian host, releasing infective trypomastigotes in feces near the bite wound or mucosae. Infective trypomastigotes enter the mammalian host, penetrating intact mucous membranes, including conjunctiva, or orally through the intestinal tract after food-borne exposure. Trypomastigotes invade cells and replicate near the site of infection, differentiating into intracellular amastigotes. Amastigotes replicate via binary fission within parasitophorous vacuoles, escape into the cytoplasm, and differentiate into trypomastigotes. Trypomastigotes are released from the cell, reaching the bloodstream. Triatome insects become infected through the ingestion of circulating trypomastigotes in mammalian blood meals, transform into epimastigotes within the triatome midgut, and undergo final differentiation into infective trypomastigotes within the insect hindgut. Kevin J. Esch, and Christine A. Petersen Clin. Microbiol. Rev. 2013; doi:10.1128/CMR.00067-12