Amoebas cause diseases such as amoebic dysentery, amoebic meningoencephalitis, amoebiasis and amoebic liver abscess. Some of these disorders have symptoms that are silent or mild. Others are life-threatening.
Amoebic dysentery is caused by eating food or drinking water that has been contaminated by amoebic cysts found in raw sewage. A symptom of this disease is bloody, explosive and foul-smelling diarrhea. The diarrhea may be such that the patient also experiences dehydration. The patient might also experience fever, fatigue, chills, weight loss and severe pains in the abdomen.
If amoebic dysentery is untreated, the amoebas can be carried to the liver, where they can cause abscesses. The symptoms are much the same as they are for amoebic dysentery, though the patient also suffers jaundice and an enlarged liver. Amoebiasis is also caused by amoebas, but the symptoms can be mild or even silent.
Amoebic meningoencephalitis is a rare but terrible disease caused by the Naegleria fowleri amoeba. In this disease, the amoebas attack the central nervous system. The first symptoms are the person's loss of the sense of smell. The symptoms then progress to the symptoms of encephalitis, which are rigid neck muscles, headache, nausea, convulsions, delirium and a coma that can proceed to death.