Primary amoebic meningoencephalitis (PAM) is a rare and often fatal infection of the brain caused by a free-living amoeba called Naegleria fowleri. This protozoan organism is commonly found in warm freshwater environments, such as lakes, hot springs, and poorly maintained swimming pools. PAM occurs when an individual becomes exposed to Naegleria fowleri-infected water through their nasal passages, allowing the amoeba to enter the nasal mucosa and travel to the brain.
Once inside the brain, Naegleria fowleri rapidly multiplies and attacks the central nervous system, causing severe inflammation and tissue destruction. The initial symptoms of PAM closely resemble bacterial meningitis, including headache, fever, stiff neck, nausea, and vomiting. As the infection progresses, individuals may experience seizures, hallucinations, coma, and ultimately death, typically within a week of symptom onset.
Due to its fast progression and high fatality rate, early diagnosis and treatment of PAM is crucial. However, it is often difficult to diagnose PAM accurately, as its symptoms can mimic other more common illnesses. Treatment options include antifungal medications and compounds like amphotericin B, which are effective against the amoeba, but success rates remain low.
Prevention is the best defense against PAM. It is recommended to minimize exposure to freshwater environments that may harbor Naegleria fowleri, especially during hot summer months when water temperatures are more favorable for the amoeba's growth. Avoiding activities that involve putting the head underwater or inhaling water through the nose is also encouraged. Proper chlorination and maintenance of swimming pools and other water facilities can help reduce the risk of infection.
