Unraveling the Brain-Eating Amoeba Threat: Genotyping & Surveillance

Naegleria fowleri, the ＂brain-eating amoeba,＂ causes the fatal Primary Amoebic Meningoencephalitis (PAM). In this study, CSF samples from 80 suspected PAM patients were analyzed for key indicators like leukocyte count, glucose, protein, and microscopy. While 79 tested negative, one was confirmed positive for N. fowleri through PCR and microscopy. Surprisingly, common CSF tests (high protein, low glucose, elevated TLC) failed to distinguish PAM from other types of meningitis, highlighting the need for PCR and wet prep microscopy for accurate diagnosis. The positive sample was cultured on non-nutrient agar (NNA), and mitochondrial sequencing identified N. fowleri. Genotyping revealed N. fowleri genotype 2, marking the first report in Pakistan. Environmental surveillance of Karachi’s water supplies identified N. fowleri in 11 locations, including the patient’s home, linking contaminated water to infection. Since 2011, all PAM cases in Karachi have been reported here. This study provides essential genotypic data and urges improved water quality monitoring, public awareness, and infrastructure upgrades to combat this deadly disease.