Year: 2025
Type: article
Abstract: The outbreak of amoebic meningoencephalitis in Kerala: A wake-up call Kerala, a South Indian State, has been witnessing a marked rise in suspected/confirmed severe central nervous system (CNS) infections caused by freeliving amoebae (FLA) during 2024-2025 with reports indicating a total of 129 cases and 26 deaths as of October 18, 2025 1 .Districts like Kollam, Thiruvananthapuram, Kozhikode, and Malappuram are particularly affected.These infections are being increasingly reported and are associated with high mortality.This unusual rise in cases has prompted the State government to rapidly expand testing capacity for early diagnosis and institution of aggressive therapy 1 .Free living amoebae viz.Naegleria fowleri, Acanthamoeba genotypes T1-T23, Balamuthia mandrillaris and various other genera, are ubiquitous organisms that live in fresh or warm brackish water, lakes, ponds, irrigation canals, soil, etc.While all of the above named species cause rare central nervous system infections, Acanthamoeba is also associated with vision-threatening keratitis and disseminated disease.To date, more than 20 genotypes (T1-T23) of Acanthamoeba have been described, of which a subset, notably genotypes T1, T2, T3, T4, T5, T10, T12, and T18, are implicated in human disease.Among these, the T4 genotype is the most commonly isolated from both clinical and environmental samples and is considered the predominant pathogenic genotype worldwide [2][3][4][5][6] .N. fowleri, the only pathogenic species of genus Naegleria, causes an acute fulminant meningoencephalitis (Primary amoebic meningoencephalitis, PAM) that is associated with high mortality.Acanthamoeba and Balamuthia lead to subacute to chronic infection (Granulomatous amoebic encephalitis) with relatively better survival.The infections are clinically indistinguishable from bacterial or viral meningitis or encephalitis.Naegleria trophozoites gain entry into the brain mainly through the naso-olfactory route and can affect healthy individuals.Acanthamoeba or Balamuthia infection is primarily acquired through breaks in the skin and spread via a hematogenous route, or via naso-olfactory route or inhalation and mainly affects immune compromised
Author: Sumeeta Khurana
Language: English
Subfield: Endocrinology
Domain: Life Sciences
Open Access status: diamond
OpenAlex ID: W7117369140