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Health officials are investigating outbreak of rare rat virus in MN

13 people in eight states have gotten sick.

Minnesota is among the states where health officials are investigating a rare rat virus.

The Seoul virus – a rare type of hantavirus carried by wild Norway rats across the world – was first reported last month, with health officials saying eight people in Illinois and Wisconsin were infected after being exposed to rodents at breeding facilities.

The two people in Wisconsin got sick while operating home-based rat breeding – their rats traced back to two ratteries in Illinois, where six people had tested positive for the Seoul virus, the Centers for Disease Control and Prevention says.

Lab tests have now confirmed 13 human cases of the Seoul virus, the CDC said in an update Thursday, noting there are eight states – including Minnesota – where humans or rats have tested positive for the virus.

The Star Tribune reports no human cases have been reported in Minnesota as of the end of January, but the outbreak has put rat owners and breeders in the Twin Cities on high alert.

Minnesota is among the 16 states with ratteries that are being investigated by the CDC and local health officials, the CDC says. Local health officials told the Star Tribune the outbreak here seems to be contained to three breeders that got their rats from suppliers in Wisconsin and Illinois – two of them tested negative for the virus.

The Rat Palooza Rattery in Wright County posted on its Facebook page earlier this month saying two of its rats tested positive for the virus, so it was put on quarantine until all of its rats test negative for the virus. On Thursday, the rattery gave an update saying it tested all 66 of its rats, but it will have to wait two weeks for the results.

About the Seoul virus

The Seoul virus is a rare form of of hantavirus – really, any form of hantavirus is pretty rare in the U.S.

Hantavirus is typically spread by rodents – however infected rats will likely look healthy. People can get sick having contact with, or being in close proximity to infected rodents, or their urine and droppings. You can also get it from being bitten by an infected animal. It’s not spread from person to person, though.

The U.S. had it’s first known hantavirus outbreak in 1993, and several otherwise healthy people died from it. But that was a totally different form of the disease called Sin Nombre.

According to the CDC, the Seoul virus only has a 1 percent mortality rate, compared to the Sin Nombre virus’ 50 percent.

The Wisconsin Department of Health Services says symptoms may include fever, chills, nausea, intense headaches, back and abdominal pain, chills, blurred vision, redness of the eyes, flushed face, or rash. In severe cases, infection can lead to renal disease. However, some people don’t experience any symptoms.

Of the cases reported in Wisconsin and Illinois last month, one person was hospitalized, but has since recovered, and five of the six people infected in Illinois showed no signs of illness.

If you’ve had contact with rats recently obtained from a rat breeder and are experiencing any of these symptoms, call your doctor immediately.

Wisconsin health officials recommend practicing good hygiene with pets, like washing your hands after playing. You can get more tips here and here.

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