Leptospirosis is a zoonotic infection predominantly affecting marginalized populations in tropical regions, often resulting from exposure to contaminated water or contact with animal reservoirs, especially rodents. The disease typically manifests in a biphasic nature; beginning with an incubation period ranging from several days to a few weeks, followed by a septicaemic phase, an interphase where symptoms resolve temporarily, and finally an immune phase. While most infections are mild, approximately 10% progress to severe disease involving multi-organ complications, typically manifesting during the immune phase. We report a case of myocarditis and septic shock during the acute phase of leptospirosis. © The Author(s) 2026