Amoebiasis

Amoebiasis is an intestinal infection caused by the parasite Entamoeba histolytica, spread through contaminated food and water. It can range from no symptoms to severe bloody diarrhoea, and rarely spreads beyond the gut to form abscesses in the liver.

• Many infections cause no symptoms
• Gradual onset of loose stools, sometimes with blood and mucus, over days to weeks
• Abdominal cramping and bloating
• Weight loss with prolonged infection
• Fever and right upper abdominal pain if the parasite spreads to form a liver abscess (amoebic liver abscess)

• Caused by the parasite Entamoeba histolytica.
• Spread through the faecal-oral route via water or food contaminated with the parasite's cysts.
• Risk is increased by poor sanitation, unsafe water supply, and inadequate food and hand hygiene.

• Diagnosed through stool microscopy identifying Entamoeba histolytica cysts or trophozoites, ideally on a fresh stool sample.
• Stool antigen testing, where available, improves diagnostic accuracy over microscopy alone.
• Abdominal ultrasound is used if amoebic liver abscess is suspected, showing a characteristic fluid collection in the liver.

Intestinal amoebiasis is treated with metronidazole (or tinidazole where available) for 7–10 days to clear the active infection.

This is typically followed by a second, luminal-acting medicine (such as diloxanide furoate, where available) to eliminate any remaining cysts from the gut and prevent relapse or ongoing transmission.

Amoebic liver abscess is treated with the same antiamoebic antibiotic course; larger abscesses or those not responding to medicine alone may require drainage, usually guided by ultrasound, at a facility with the necessary capacity.

Adequate rehydration is provided throughout treatment, particularly if diarrhoea is significant.

• Drink water from safe sources, or boil or treat water before drinking.
• Wash hands with soap after using the toilet and before preparing or eating food.
• Wash fruits and vegetables thoroughly, and cook food adequately.
• Ensure proper disposal of human waste and access to safe sanitation.