Public Health Ontario has been working with the Ministry of Health and Long-Term Care (MOHLTC), Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA), Public Health Agency of Canada (PHAC), Centers for Disease Control and Prevention (CDC) and public health units to investigate an outbreak of Seoul virus (SEOV) infections among people exposed to infected rats in several rat-breeding facilities in Ontario and the USA since December 2016.
Members of the public concerned about SEOV should contact their health care provider. Health care providers concerned about SEOV should refer to the testing and guidance information below or contact their local public health unit.
Seoul virus (SEOV) is a rodent-borne hantavirus found worldwide, with Norway rats and black rats as natural hosts. SEOV does not cause disease in rats; rather the virus causes a life-long infection and shedding of the virus in urine, saliva and droppings. Human infection with SEOV occurs after being exposed to urine, droppings or saliva of infected rats, including contact with their bedding or from the bite of an infected rat. SEOV is not spread from person to person.
SEOV infections can present with fever, headache, back and abdominal pain, chills, nausea, blurred vision, flushing of the face, inflammation or redness of eyes and rash. Rarely, SEOV can cause a syndrome referred to as hemorrhagic fever with renal syndrome (HFRS). HFRS can present with symptoms and signs of bleeding, shock and kidney failure. Symptoms of SEOV infection usually begin within 1–2 weeks (rarely up to 8 weeks) after exposure. Complete recovery can take weeks or months.
There is no effective treatment for SEOV infection. People handling rats (as pets or as reptile or amphibian feed) should take precautions to minimize risk of infection, including hand hygiene and cleaning up after rats.
For additional information, please see Seoul virus infection: Information and guidance for rat handlers.