The image shows a cyst, trophozoite, and flagellate. This organism is found in warm bodies of water like hot springs and man-made lakes and ponds; it is not seen in seawater. The typical presentation is a previously healthy child or adult with freshwater exposure in the last 2 weeks who presents with acute onset of headache, fever, neck stiffness, nausea, and vomiting. Uniquely, sense of smell and taste are affected. Antibiotics do not help, and patients then develop seizures, ataxia, cranial nerve palsies, confusion, and coma. This disease is fatal in 95% of cases within 4-6 days due to brain herniation.
Challenge: What's the pathogen?
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