Question

Write about cause, symptoms and modes of transmission of Amoebiasis.

Answer 1

$Cause$:

Amoebiasis is caused by parasite Entamoeba histolytica. Several protozoan species in the genus Entamoeba colonize humans, but not all of them are associated with a disease. It exists in two forms- Vegetative (trophozoite) and cystic forms (cyst). Trophozoites multiply and encyst in the colon. The cysts are excreted in stool and are infective to humans. Cysts remain viable and infective for several days in faeces, water, sewage and soil in the presence of moisture and low temperature.

$Symptoms$:

The clinical spectrum ranges from asymptomatic infection, diarrhoea and dysentery to fulminant colitis and peritonitis as well as extra-intestinal amoebiasis. Acute amoebiasis can present as diarrhoea or dysentery with frequent, small and often bloody stools. Chronic amoebiasis can present with gastrointestinal symptoms plus fatigue, weight loss, and occasional fever. Extra-intestinal amoebiasis can occur if the parasite spreads to other organs, most commonly the liver where it causes an amoebic liver abscess. Amoebic liver abscess presents with fever and right upper quadrant abdominal pain.

$Mode$ $of$ $transmission$:

Transmission occurs via:

• A faecal-oral route, either directly by person-to-person contact or indirectly by eating or drinking faecally contaminated food or water.
• Sexual transmission by oral-rectal contact is also recognized especially among male homosexuals.
• Vectors such as flies, cockroaches, and rodents can also transmit the infection.