It's been almost three weeks since a team of veterinarians and health officials wearing hazmat suits came into Debbie Fratini's Chicago-area home and killed all 31 of her beloved pet rats.

Although Fratini said at the time that she knew it was the right thing to do, she is still heartbroken.

The culprit is Seoul virus, a type of hantavirus that can be transmitted from pet rats to humans. The outbreak first came to attention in December and is believed to have started in Illinois and Wisconsin. Minnesota now is one of 15 states being investigated by the Centers for Disease Control and Prevention (CDC) and state health officials.

Pet rat owners and breeders in the Twin Cities area have been alarmed and frightened since last month, when reports and rumors began circulating on rat forums, blogs and websites that their pets might be confiscated and killed.

Amy Pass of Minneapolis has two pet rats: Sonnet and Haiku. Both were purchased from a Twin Cities breeder whose rats have since tested negative for the virus. "I'm having a hard time knowing how concerned to be," she said Thursday. "Nobody's been sick in our house."

Still, Pass is making sure to follow the CDC's precautions, such as washing hands after handling the rats and keeping cages, bedding and toys away from areas where food is served or people bathe.

Pass said rats make great pets. "They're like little puppies," she said. "They have personalities and they have affection for you. You get to know their little quirks."

The CDC said the general public is at "extremely low risk" from the Seoul virus, which cannot pass from person to person. Only a few cases of actual illness have been reported in the United States. Symptoms are similar to the flu and may include fever, severe headache, back and abdominal pain, chills, blurred vision, redness of the eyes or rash.

The Minnesota Department of Health (MDH) issued a statement in late January saying that no human Seoul infections have been reported here. MDH spokesman Doug Schultz said the situation in Minnesota appears to be confined to three breeders who received rats from facilities in Wisconsin and Illinois.

Two of those three ratteries tested negative for the virus, he said. A couple of rats at a breeder in Wright County tested positive. Those rats were killed and further testing is ongoing. The rattery is under quarantine "until no positive rats are found," Schultz said. Veterinarians and health care providers have been alerted about the virus, he said.

The Wright County breeder, who was not identified by the Health Department, appears to be Rat Palooza in Howard Lake. On its Facebook page, the owner wrote Thursday that, "The Rattery is having all 66 rats tested today for the Seoul virus. Fingers crossed everyone is negative and this quarantine can be lifted off soon."

Nikki Stonerr runs Disco's Rats in Chaska.

"This virus is a huge blow to the pet rat community," she said in an email. "We have been trying to educate people on how great of pets rats can make, and with the media portraying rats as dirty, disease-infested creatures, this hurts the rat business, rat breeders and rat owners. Our beloved pets are not wild animals, they are part of our family.

"This is a case of a pet rat breeder being uncautious about quarantine rules when bringing in new animals and mixing wild rats with pet ones, which should not be done," she wrote.

A Wisconsin woman who breeds pet rats became ill in December and was hospitalized. Doctors there notified the CDC, which traced the virus to two breeders in Illinois, both of whom had sold rats to the Wisconsin woman.

Humans can show no signs of illness but still test positive for antibodies to the virus. Infected rats do not become sick, but can shed the virus through urine, feces and saliva for many months.

Fratini said she has been breeding rats for 16 years and bought three from an infected rattery in November.

She didn't get sick, but doctors found virus antibodies in her blood from both short-term and long-term exposure, she said, and was told that if any of her rats tested positive, all would be killed. Rather than subject them to testing, she agreed to have them killed.

"I was falling apart, crying, these are my pets," she said.

Now Fratini is angry, too. The policy was apparently changed to spare, quarantine and retest rats that test negative for the virus.

For more information on the Seoul virus, go to http://bit.ly/2kY2fWm.

Pat Pheifer • 612-673-7252