Seoul Virus

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

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.

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.

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

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.

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

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: https://www.cdc.gov/rodents/cleaning/index.html.

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

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

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.

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.

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

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.

• CDC Cleaning Up After Rodents
• CDC Hantavirus Information
• CDC Hemorrhagic Fever with Renal Syndrome (HFRS) Information
• CDC Touching Pet Rodents Don’t Get Sick
• IDPH Seoul Virus Press Release (1-19-17)
• Schools – Safe Rat Handling (pdf)
• Pet Stores – Safe Rat Handling (pdf)
• Animal Shelters and Rescue – Safe Rat Handling (pdf)
• Health Guidelines for Rat Care (pdf)
• Rat-Borne Diseases (pdf)
• Reducing Risk of Human Infection from Pet Rodents (pdf)