*some encyst in large intestine
*cysts are excreted from anus
===clinical manifestation===
*incubation a few days to years
*80% of infection are asymptomatic
*mild, extensive, extreme
*large intestine ulcer
**flask-shaped ulcer in histpahology
===morphology===
**3:1 in developing countries
**10:1 in developed countries
==''Entamoeba coli''==
*6 nuclei in cyst