Neuromelioidosis in endemic regions: epidemiology, genomic insights, diagnosis, treatment, and public health lessons from Tamil Nadu

Abstract Neuromelioidosis is an uncommon but severe neurological manifestation of melioidosis caused by Burkholderia pseudomallei an environmental Gram-negative bacterium endemic to tropical and subtropical regions. Neurological involvement occurs in approximately 2–5% melioidosis cases, although substantially higher proportions have been reported from selected tertiary-care cohorts in southern India. Globally, melioidosis is estimated through modelling studies to cause approximately 165,000 cases and 89,000 deaths annually, with major burdens in Southeast Asia, Northern Australia and increasingly recognized endemic regions. Recent neuromelioidosis outbreaks in Tamil Nadu have further highlighted diagnostic, epidemiological, infection-control and public health challenges. This review critically examines current evidence on the epidemiology, pathogenesis, genomic determinants, clinical manifestations, diagnosis, treatment and public health implications of neuromelioidosis. Particular attention is given to bimA variants and advances in whole-genome sequencing, core-genome multilocus sequence typing and SNP-based phylogenetics for understanding neurotropism, transmission, and outbreak investigation. Diagnostic challenges are discussed in relation to variable specimen yield, frequently negative cerebrospinal fluid cultures, serological cross-reactivity, neuroimaging, molecular diagnostics and the emerging adjunctive role of metagenomic next-generation sequencing. Current antimicrobial treatment, neurological management, relapse prevention and antimicrobial stewardship are also reviewed. Finally, priorities including strengthened laboratory capacity, integrated clinical–environmental genomic surveillance, rapid diagnostics, vaccine development, host-directed therapies and international One Health surveillance networks are highlighted. A more standardized and coordinated approach is required to define the true burden of neuromelioidosis and improve its early recognition, management and prevention.