 <unk> the site of the bite causes the trypomastigotes to enter the host through the wound , or through intact <unk> membranes , such as the <unk> . Once inside the host , the trypomastigotes invade cells , where they differentiate into intracellular amastigotes . The amastigotes <unk> by binary fission and differentiate into trypomastigotes , which are then released into the bloodstream . This cycle is repeated in each newly infected cell . <unk> resumes only when the parasites enter another cell or are ingested by another vector . ( See also : Life cycle and transmission of T. cruzi ) 
