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Seoul Virus

What is Seoul virus?

Seoul virus is a virus carried by rats. It is a milder type of hantavirus.

How do humans become infected with Seoul virus?

Seoul virus is carried and transmitted by rats. The virus has been found in both pet rats and wild rats around the world. People can become infected with this virus after coming into contact with urine, droppings, or saliva of infected rats. When fresh rats urine, droppings, or nesting materials are stirred up, such as during vacuuming or sweeping, pieces of the virus can get into the air. Transmission may also occur when infected urine or feces come into direct contact with cuts or other broken skin, or into the eyes, nose, or mouth. In addition, individuals who work with live rats can be exposed to Seoul virus through bites from infected animals.

Seoul virus is not known to be transmitted from one person to another.

What are the symptoms of Seoul virus infection?

Symptoms of Seoul virus infection usually develop within one to two weeks after exposure to the virus. Not everyone infected with Seoul virus will have symptoms. In rare cases, symptoms may take up to eight weeks to develop. Initial symptoms begin suddenly and may include intense headaches, back and abdominal pain, fever, chills, nausea, and blurred vision. Individuals may have flushing of the face, inflammation or redness of the eyes, or a rash. In more severe cases, symptoms can include low blood pressure, acute shock, vascular leakage, and acute kidney failure, which can cause severe fluid overload and lead to hemorrhagic fever with renal syndrome (HFRS). Seoul virus infections are usually mild to moderate. Complete recovery can take weeks or months.

How is Seoul virus infection diagnosed?

Blood tests are used to confirm a diagnosis of Seoul virus infection.

How is Seoul virus infection treated?

There is no specific treatment for Seoul virus infection. Supportive care is used for patients with infections. This includes careful management of the patient’s fluid (hydration) and electrolyte (e.g., sodium, potassium, chloride) levels, maintenance of oxygen and blood pressure levels, and appropriate treatment of any secondary infections. In severe cases, dialysis may be required.

Is Seoul virus infection ever fatal?

Death due to Seoul virus infection is rare, but is estimated to occur in 1-5 percent of patients.

How is Seoul virus infection prevented?

Avoiding contact with rats and rat control is key to preventing Seoul virus infections. Wild rats near human communities should be controlled, and wild rats should be excluded from homes. Individuals should avoid contact with rat urine, droppings, saliva, and nesting materials. It is important to use disinfectant and follow guidelines for cleaning rat-infested areas. More information on how to safely clean up after rats can be found on CDC’s webpage:

Where is Seoul virus found?

Seoul virus is found worldwide. Human infection due to Seoul virus is rare in the United States.

Which rats carry the hantaviruses that cause HFRS in humans?

Primarily, the brown or Norway rat (Rattus norvegicus) carries Seoul virus, although other species of rat can also carry it.

How do rats get Seoul virus?

Seoul virus is found in the urine, feces, and saliva of recently infected rats. Rats can become infected with Seoul virus through wounding or biting other rats and after coming in contact with the urine or feces of infected rats.

How do I know if my pet rat is infected with Seoul virus?

Rats do not show symptoms of disease when they are infected with Seoul virus. The only way to know if they are infected is through laboratory testing.

Is this virus the same one that causes Hantavirus Pulmonary Syndrome (HPS)?

No. HPS is a different syndrome caused by different viruses. HPS is typically more severe than HFRS.

What should I do if I think I may have symptoms?

Seek prompt medical attention if you think you may be infected with Seoul virus. Tell your health care provider about your symptoms and explain your contact with rats.