What are the symptoms of contracting a brain-eating amoeba parasite?
Jul 04, 2025
Source: Cainiu Health
Dr. Shen Yonghua
Introduction
"Brain-eating amoeba" usually refers to the amoeba parasite. After the amoeba parasite infects the intestines, it stimulates the intestinal mucosa, causing inflammation, which leads to mild to severe abdominal pain, typically concentrated in the lower abdomen. This is often accompanied by diarrhea and increased frequency of bowel movements. Some patients may also experience digestive system disturbances such as bloating and increased bowel sounds. If the above symptoms occur, timely medical consultation and diagnostic examination are necessary.
The term "brain-eating amoeba" usually refers to Naegleria fowleri. After parasitizing the body, this amoeba generally causes symptoms such as gastrointestinal discomfort, fever with chills, mucoid bloody stools, liver pain, and neurological symptoms. If any abnormalities occur, prompt medical attention is recommended. Detailed explanations are as follows:
1. Gastrointestinal discomfort: After parasitizing the intestines, the amoeba irritates the intestinal mucosa, causing inflammation, leading to abdominal dull or cramping pain, typically localized in the lower abdomen. Diarrhea often accompanies this pain, with increased frequency of bowel movements. Some patients may also experience bloating and hyperactive bowel sounds, indicating gastrointestinal dysfunction.
2. Fever with chills: The infection triggers an immune response, stimulating the body's temperature-regulating center, resulting in elevated body temperature. Patients commonly develop fever, with temperatures reaching 38°C or higher, accompanied by chills, fatigue, and significantly reduced physical endurance.
3. Mucoid bloody stools: The amoeba erodes the intestinal wall, causing local ulcers and bleeding, resulting in mucus and blood mixing with the stool. The stool appears dark red or like jam, has a viscous consistency, and emits a distinctive foul odor, clearly different from the stool of ordinary diarrhea.
4. Liver pain: If the amoeba spreads to the liver through the bloodstream, it can cause amoebic liver abscess. Patients may experience persistent distending pain in the upper right quadrant of the abdomen, with pain intensity increasing as the condition progresses. Some patients may have hepatomegaly (enlarged liver), with increased pain upon palpation of the liver area.
5. Neurological symptoms: When the amoeba enters the brain through the nasal cavity, it can cause primary amoebic meningoencephalitis. Early symptoms include headache, nausea, and vomiting, followed by fever and neck stiffness. The condition progresses rapidly, potentially leading to severe neurological symptoms such as confusion, seizures, or even coma.
If any of the above symptoms appear, timely medical evaluation and diagnosis are necessary. In daily life, maintaining dietary hygiene is important, including avoiding consumption of unwashed or undercooked food and not drinking untreated water.
