Unmasking the silent nocturnal killer: a comprehensive review of common krait (Bungarus caeruleus) venom, neurotoxicity, and challenges in antivenom therapy in India

Snakebite envenomation remains a major global health issue, with India experiencing the highest deaths, mainly caused by the “Big Four” snakes. The common krait (Bungarus caeruleus), a nocturnal predator that is often overlooked, accounts for a disproportionate number of fatalities, especially in rural and peri-urban areas. To synthesize current evidence on the epidemiology, clinical features, venom composition, and therapeutic challenges associated with Bungarus caeruleus, and to identify key gaps that limit effective management and antivenom development. This review synthesizes data from clinical reports, epidemiological records, proteomic and transcriptomic research, and structural database analyses. It also reviews public protein repositories, such as UniProt and GenBank, to assess venom annotation in the Indian krait. Additionally, relevant papers published were identified through a comprehensive literature search using Medline/PubMed/PMC, Scopus, Web of Science, Google Scholar, and the reference lists of pertinent articles. Krait envenomation is characterized by delayed yet rapidly progressing neuroparalysis that often results in respiratory failure. Venom analyses show a dominance of presynaptic PLA2 isoforms, β-bungarotoxins, and three-finger toxins, with significant geographic variability across India. Structural databases reveal a notable lack of characterized krait toxin structures, which hampers rational antivenom development. Epidemiological trends, especially in Tamil Nadu, indicate an increase in krait bites driven by ecological and healthcare system factors. Current polyvalent antivenoms have limited effectiveness against regionally diverse krait venoms, highlighting gaps in venom representation and in the annotation of toxins in public repositories. Common krait envenomation remains a major clinical and public health issue in India. Reducing high morbidity and mortality calls for region-specific venom banks, enhanced molecular analysis of understudied krait toxins, advanced therapeutics, and stronger healthcare systems. An integrated approach that combines molecular toxicology, effective clinical management, and comprehensive public health strategies is vital to address the increasing burden. This review provides a comprehensive overview of the epidemiology, venom biology, clinical challenges, and therapeutic gaps associated with Bungarus caeruleus envenomation in India. It combines field data, health records, and proteomic and structural analyses to highlight major deficiencies in current antivenoms, especially the oversight of significant regional venom variation and limited molecular information on key toxins. The article points out the inadequate protection provided by existing polyvalent antivenoms, which leads to preventable deaths in rural areas with limited ventilatory support. It emphasizes the need for region-specific venom banks, improved antivenom development, better toxin characterization, and enhanced rural healthcare to reduce krait-related mortality.