What is epidemic hemorrhagic fever?

Epide­mic hemorrhagic fever (EHF) is a group of zoonotic viral diseases caused primarily by hantaviruses, which belong to the family *Hantaviridae*. These viruses are naturally maintained in rodent reservoirs—such as deer mice, bank voles, and striped field mice—and are transmitted to humans through inhalation of aerosolized excreta (urine, feces, or saliva), direct contact with infected rodents or their nesting materials, or, less commonly, via bites. Human-to-human transmission is extremely rare and not considered epidemiologically significant.

Clinically, EHF encompasses several related syndromes, including Hemorrhagic Fever with Renal Syndrome (HFRS), predominantly found in Asia and Europe, and Hantavirus Pulmonary Syndrome (HPS), primarily reported in the Americas. While both share a common viral etiology, they differ markedly in pathophysiology and clinical presentation: HFRS is characterized by acute kidney injury, thrombocytopenia, increased vascular permeability, and potential hemorrhagic manifestations; HPS presents with rapid-onset pulmonary edema, respiratory distress, and cardiopulmonary compromise due to capillary leak in the lungs.

Diagnosis relies on clinical suspicion supported by laboratory testing—including IgM ELISA, PCR for viral RNA detection, and sometimes immunohistochemistry in tissue samples. There is no specific antiviral therapy approved for hantavirus infections; management remains supportive and intensive, focusing on fluid balance, renal replacement therapy when indicated, oxygenation support, and careful hemodynamic monitoring. Early recognition and prompt referral to an appropriate medical facility significantly improve outcomes. Prevention centers on rodent control, environmental sanitation, and personal protective measures in endemic or high-risk settings.