Kjersti Nelson and her two kids had the whole day planned out at the Minnesota State Fair: 10 a.m. robot exhibit, noon physics show, and then off to see the barn animals!

Then at 9:50 a.m., the Minneapolis mom got a text message from a friend that gave her pause.

"Stay away from pigs!"

The message reflected an underlying dilemma as the Minnesota State Fair celebrated its opening day: Whether to visit the big hogs at the Swine Barn and the little piglets at the Miracle of Birth Center, or to skip the perennial fair favorites over concerns about a new influenza strain that spreads from pigs to humans.

More than 200 cases of the H3N2v influenza have been reported in the U.S. this summer, almost all involving children who visited or exhibited pigs at state or county fairs.

Concern heightened in Minnesota this week when the state Department of Health reported one confirmed case and one probable case involving siblings who visited a pig market in Dakota County. A prominent infectious disease expert, Michael Osterholm at the University of Minnesota, recommended removing pigs from the fair this year. But state health authorities and fair officials decided to proceed with the swine exhibits, while issuing precautions to fairgoers.

On Thursday morning, tradition seemed to prevail over jitters -- fairgoers were often shoulder to shoulder in the swine barn and jostling for peeks at the new piglets in the birth center.

Molly Nelson of Shoreview took her four school-age kids to the barn despite "suggestions" from her mother and sister to stay away.

"They like seeing all the animals, and especially the big pigs," said Nelson -- who had her kids wash their hands in sinks at the Swine Barn exit and apply hand sanitizer as they left.

Erica Ohern's first stop with her husband and two children was the birth center: "Living in the suburbs, we don't get to see farm animals very often," the Farmington mother said.

Fair spokeswoman Brienna Schuette said it would be "only natural" for fewer people to be at the two buildings. But the opening-morning crowds appeared about normal, said Leah Addington, leadership development coordinator for the Minnesota FFA Association.

Addington did, however, notice fewer visitors bringing food into the birth center. That was one of the public health recommendations posted at the door.

At both buildings, special signs encouraged hand-washing and asked visitors to not bring in pacifiers or touch their mouths while in the buildings. Health officials also asked people at greater risk of flu complications -- such as pregnant women, children younger than 5, and the elderly -- to considering skipping the exhibits.

Pigs or kiddie rides?

At midmorning in the Swine Barn, 4-H teens caring for the pigs weren't all that concerned.

"It's not as bad as the other one was," said Bradley Hillard, 15, of Tyler, Minn., referring to the global H1N1 swine flu outbreak in 2009.

The latest strain hasn't produced many severe infections. Neither of the siblings in Dakota County needed hospital care or suffered complications, according to the state Health Department. So far, the new flu strain resembles ordinary seasonal flu, with symptoms that include fever, cough and a runny nose.

Amber Butcher, 16, of Brownton, Minn., wasn't exactly following the guidance about keeping food out of the swine barn as she polished off her third Mountain Dew of the fair by 10:30 a.m.

"I've been putting a lot of hand sanitizer on," she said, "but that's about it."

Some fairgoers reluctantly broke with tradition and planned to skip the pigs.

One of Ben Dwyer's 4-year-old twins suffers from food allergies and asthma, so staying away seemed like the safest choice for girls who had other priorities anyway.

"They've been talking about the kiddie rides the whole way down here," said the Elk River dad.

Brian Brezinka's 11-year-old daughter, Lydia, wanted to see the "fat pigs," and his 11-year-old niece, Acadia King, wanted to see the "baby pigs." But the Falcon Heights man had other plans. "We usually go there every year," he said. "This year? Nah."

After her warning text from a friend, Kjersti Nelson decided to keep to her schedule and take her 7- and 5-year-old kids to see the pigs.

"There's danger and there's also hype," she said. "This is probably somewhere between the two."

Jeremy Olson • 612-673-7744