Amoebic encephalitis is a rare yet devastating central nervous system infection, triggered by free-living amoebae commonly found in freshwater sources like lakes and rivers. Disturbingly, as of September 17, 2025, Kerala has reported 19 deaths and around 70 cases of amoebic meningoencephalitis this year alone, with many individuals still undergoing treatment.
Here are ten crucial things to understand about amoebic meningoencephalitis:
- This infection manifests in two primary forms: Primary Amoebic Meningoencephalitis (PAM) and Granulomatous Amoebic Encephalitis (GAE).
- PAM is specifically caused by Naegleria fowleri, an amoeba that thrives in warm freshwater environments such as lakes, ponds, and rivers. In rare instances, it can also be found in poorly maintained swimming pools.
- Often referred to as the ‘brain-eating amoeba’, this single-celled organism can infect and destroy brain tissue, leading to severe swelling. While infections are uncommon, they are typically fatal, with survival rates as low as 3%.
- The amoeba enters the body through the nose, traveling directly to the brain where it causes tissue destruction and swelling. Children appear to be more susceptible to this infection. It is important to note that the infection does not spread from person to person, nor does swallowing water containing the amoeba lead to infection.
- PAM is particularly concerning because it usually affects otherwise healthy children, teenagers, and young adults, often resulting in rapid onset and delayed diagnosis, contributing to its high fatality rate.
- Initially, PAM symptoms can be mistaken for bacterial meningitis, while GAE symptoms might mimic other serious conditions like a brain abscess or encephalitis. Both forms are frequently fatal, though a few survivors have been documented. The Kerala government has implemented a treatment protocol aimed at earlier diagnosis and intervention.
- Patients typically have a history of engaging in water activities like swimming, diving, bathing, or playing in warm, often stagnant, freshwater during the preceding one to nine days. However, some cases have been reported without such a known history.
- Deadly Naegleria species are prevalent in soil and various freshwater or brackish water bodies (lakes, rivers, ponds). They are sensitive to extreme environmental conditions like dryness and pH levels, and cannot survive in seawater.
- Diagnosis of the infection can be performed using PCR tests on cerebrospinal fluid. However, due to the rarity of PAM, detection can sometimes be challenging.
- To help prevent infection, experts suggest holding your nose or wearing nose clips when jumping or diving into freshwater. Keeping your head elevated while entering warm water is also recommended. It’s best to avoid digging in shallow waters. For clearing nasal passages, use distilled or boiled water. Additionally, proper chlorination and regular cleaning of wells, tanks, and swimming pools are crucial preventive measures.