Entamoeba histolytica is a parasitic enteric protozoan and the etiologic agent
of amebic colitis and liver abscess in humans. Amebiasis is commonly acquired
through water- and food-borne transmissions and highly prevalent in tropical areas of
the world where sanitation is poor. Symptoms can be mild, including loose stools and
abdominal cramping but if the parasite invades the colon it can advance to amebic
dysentery characterized by frequent watery and bloody stools. Following colonic
invasion, trophozoites can enter the bloodstream and lymphatics and disseminate to the
liver, heart, lungs, brain, or other organs, to cause abscesses, which if left untreated can
lead to death. As treatment for amebiasis with metronidazole has adverse side effects
research into novel therapeutics and vaccines is still actively being pursued. The
present chapter summarizes the characteristics of amebiasis, their treatments and
control and the importance of water transmission.
Keywords: Amebiasis, Colitis, Cysteine proteinases, Entamoeba dispar,
Entamoeba histolytica, Liver abscess, Protozoa.
