The pathogenesis of Haemorrhagic Fever involves a complex interplay between the viral infection and the host's immune response. These viruses often target endothelial cells, leading to increased vascular permeability and, subsequently, bleeding manifestations. Clinical features vary depending on the specific virus but commonly include fever, fatigue, muscle pain, and, in severe cases, bleeding from various sites such as the gums, nose, and gastrointestinal tract. Organ failure may ensue, contributing to the high mortality associated with certain Haemorrhagic Fever viruses. Disseminated intravascular coagulation (DIC) is a common complication, where the normal blood clotting process becomes dysregulated, further contributing to bleeding tendencies. Understanding the pathophysiology and clinical manifestations is crucial for timely diagnosis and appropriate medical intervention.