Hantaan virus

Hantaan virus (HTNV) is a member of the Orthohantavirus genus within the Hantaviridae family. It is the primary causative agent of hemorrhagic fever with renal syndrome (HFRS), a severe zoonotic infection transmitted to humans through exposure to rodent excreta. The virus was first identified in the Hantan River region of South Korea, from which it derives its name.

Virology

Hantaan virus is an enveloped, negative-sense, single-stranded RNA virus with a segmented genome consisting of:

• S segment – Encodes the nucleocapsid protein (N protein).
• M segment – Encodes the glycoproteins (Gn and Gc), essential for viral entry.
• L segment – Encodes the RNA-dependent RNA polymerase (RdRp).

It belongs to the Bunyavirales order, along with other rodent-borne hantaviruses, such as Seoul virus, Puumala virus, and Dobrava-Belgrade virus.

Reservoir and Transmission

Hantaan virus is maintained in nature by rodent reservoirs, primarily:

• Apodemus agrarius (striped field mouse) – The primary host in Asia.
• Other murid rodents – Can harbor and spread the virus.

The virus is not transmitted directly between humans. Instead, humans become infected through:

• Inhalation of aerosolized virus from infected rodent urine, feces, or saliva.
• Direct contact with contaminated surfaces.
• Bites from infected rodents (rare).

Hantaan virus is endemic in China, Korea, and Russia, with sporadic cases reported in other parts of Asia.

Clinical Manifestations

Hantaan virus causes hemorrhagic fever with renal syndrome (HFRS), which progresses through five clinical stages:

• 1. Febrile phase (1–7 days) – Sudden onset of fever, chills, headache, myalgia, and nausea.
• 2. Hypotensive phase (2–5 days) – Marked by shock, vascular leakage, and tachycardia.
• 3. Oliguric phase (3–7 days) – Acute kidney injury (AKI), reduced urine output, and hypertension.
• 4. Diuretic phase (7–14 days) – Polyuria (excessive urination) as renal function recovers.
• 5. Convalescent phase (weeks to months) – Gradual resolution with fatigue and prolonged recovery.

Severe cases can lead to:

• Hemorrhagic complications – Internal bleeding, petechiae, or hemorrhagic shock.
• Multi-organ failure – If not treated promptly.

Diagnosis

Diagnosis of Hantaan virus infection involves:

• Serologic testing – Detection of IgM and IgG antibodies using enzyme-linked immunosorbent assay (ELISA).
• Reverse transcription polymerase chain reaction (RT-PCR) – Confirms viral RNA in blood or urine.
• Viral culture – Rarely performed due to biosafety concerns.
• Clinical criteria – Fever, renal involvement, and hemorrhagic signs in endemic areas.

Treatment

There is no specific antiviral therapy for Hantaan virus infection. Management is supportive:

• Fluid balance management – To prevent renal overload or dehydration.
• Blood pressure stabilization – Using vasopressors if needed.
• Hemodialysis – In cases of severe acute kidney injury.
• Pain and fever control – With acetaminophen and supportive care.

Early administration of intravenous ribavirin has shown potential benefits in reducing disease severity in some cases.

Prevention

There is no licensed vaccine for Hantaan virus in most countries, but vaccination programs exist in China and South Korea. Other preventive measures include:

• Rodent control – Reducing exposure to infected rodents.
• Proper food storage – Keeping food in sealed containers.
• Avoiding contact with rodent droppings – Wearing protective gear in endemic regions.
• Disinfection of contaminated areas – Using bleach or antiviral disinfectants.

Epidemiology

Hantaan virus is responsible for thousands of HFRS cases annually, primarily in:

• China – The highest global burden of HFRS.
• South Korea – Endemic in rural agricultural areas.
• Russia and Eastern Europe – Sporadic outbreaks in forested regions.

HFRS caused by Hantaan virus has a mortality rate of 5–15%, depending on the severity of complications.

Related pages

• Orthohantavirus
• Hemorrhagic fever with renal syndrome
• Puumala virus
• Hantavirus pulmonary syndrome
• Rodent-borne diseases