State health officials suspect three Minnesota State Fair visitors fell sick with a variation of swine flu that is common in pigs but has never been seen before in people.
One of the cases has been confirmed by the CDC, and results are pending in the other two. The three people -- a teenage girl, an elementary school-age boy and a woman in her late 70s -- have recovered.
The swine flu strain is a variation called H1N2. State deputy epidemiologist Richard Danilla says the Minnesota Department of Health had posted warnings around the swine barn in response to another swine flu strain: the H3N2 variation linked to illnesses in 300 people nationwide.
"The measures we were taking to protect against H3N2 would've protected them against H1N2 as well. We have a sign up outside the swine barn and it says if you have any of these high-risk conditions to stay out of the barn. They really shouldn't have been in the barn, yet they were, all day."
Danilla says the H1N2 strain picked up a gene from the human pandemic virus.
"It might mean that it's more transmissible to people than it has been in the past," he said. "Just like we're watching for H3N2, we're going to have to start watching for H1N2 in people who have contact with swine."
Danila says the girl and the young boy recovered without being hospitalized. Both had spent hours in the swine barn.
The third case was an older woman whose grandchildren were exhibiting pigs. Like the boy, she had underlying health conditions. The woman spent four days in the hospital.
MINNESOTA STATE FAIR: IF YOU GO
• The Minnesota State Fair is open from 6 a.m. to 10 p.m. every day in Falcon Heights, but it closes an hour early on Labor Day -- the last day.
• Regular admission is $12, $10 for seniors and children, and kids under 5 years old get in free.
• For a complete calendar of events, and schedules for the Minnesota Public Radio booth at Judson and Nelson, click here.