HFRS

Hemorrhagic fever with renal syndrome (HFRS) is a human disease caused by certain hantaviruses. It is characterized by fever, vascular leakage, and acute kidney injury, with a clinical course that can range from mild to severe. HFRS is part of the broader hantavirus infection spectrum, which also includes nephropathia epidemica (NE) in Europe and hantavirus pulmonary syndrome in the Americas.

Etiology and virology

HFRS results from infection with Old World hantaviruses, most notably Hantaan, Dobrava (also called Da Bora), and Seoul viruses, as well as Puumala virus. Each virus is associated with specific rodent reservoirs and geographic patterns. Humans acquire infection through contact with urine, droppings, or saliva of infected rodents, or through inhalation of aerosolized material. Transmission between humans is very uncommon and not a driver of outbreaks.

Clinical features and course

Incubation is typically 1–3 weeks. The illness often begins with fever, myalgias, and malaise, followed by shock and hemorrhagic manifestations in more severe cases. Acute kidney injury is a hallmark, with proteinuria and oliguria progressing to diuresis during recovery. The disease is commonly described as occurring in stages: febrile, hypotensive, oliguric, diuretic, and convalescent, though exact progression varies by virus and patient.

Diagnosis and management

Diagnosis is supported by clinical features and laboratory testing, including serology for hantavirus-specific IgM and IgG and, when needed, PCR. Differential diagnosis includes leptospirosis, dengue, and other febrile illnesses with renal involvement. There is no specific antiviral proven to be universally effective; management is supportive, including careful fluid management and renal replacement therapy if needed. Prognosis varies with the viral cause and illness severity.

Prevention

Prevention centers on reducing rodent access and exposure to their excreta, particularly in homes and workplaces. Vaccines are not widely available globally; some regions use hantavirus vaccines for high-risk populations, but routine use is limited.