More than 100 students from two 4-H programs were sent home from the Minnesota State Fair on Thursday and the rest of the groups’ events were canceled after health officials confirmed four students had come down with swine flu.

The decision to send the children home was precautionary, and state health officials said there was no great risk to the public.

There are 120 students in the 4-H Arts-In and Ambassador programs. Earlier during the fair, 17 group members developed flu-like symptoms and were sent home. Tests confirmed four of the sick children had swine flu, fair officials said in a statement.

“They are going to feel lousy for a few days and then they are going to get better,” said John Linc Stine, assistant commissioner for health protection with the state Health Department.

Health officials sent members of the two programs home early to avoid infecting a new crop of 4-H students arriving for the end of the fair, which runs through Labor Day.

“They had higher than normal rates of influenza among that group of students,” Stine said. “They had been living together for several days and would continue to be an ongoing transmission risk.”

Members of the 4-H Ambassador program teach about leadership and diversity and act as 4-H spokespeople. Ambassadors must be in at least the 10th grade and can be up to 19 years old, said Wendy Huckaby, a spokeswoman for the University of Minnesota Extension’s 4-H program. Arts-In program participants range in age from 15 to 19 years old and hold musical revues four times a day during the fair.

A sign with the message “No further 2009 Arts-In shows” written on it was posted at the performance stage Wednesday.

The students in the Ambassador and Arts-In groups typically stay at the fair during its 12-day run and live in a dormitory known as the 4-H Hilton. Huckaby said the rest of the roughly 6,200 4-H members stay for just a few days at a time.

Jerry Hammer, general manager of the Minnesota State Fair, said 4-H members who come to the fair to show livestock stay in a separate building and wouldn’t necessarily have direct contact with students in the arts program.

Stine said kids from other 4-H programs were being screened for symptoms — including a fever of 100 degrees or more, coughing, sore throats or other respiratory ailments — as they got on and off buses heading to and from the fair.

He said there are no plans to close the 4-H dormitory, which has been cleaned.

“We want people to continue to visit the 4-H building,” Stine said. “The 4-H building is perfectly safe and has been maintained in a very sanitary way. This isn’t an indication of any risk about the building.”

Last year, 1.7 million people attended the 12-day fair. So far this year, daily attendance is outpacing last year. On Tuesday, 129,423 people went to the fair, setting a new record for that day.

The confirmed swine flu cases don’t mean the fair is riskier than any other public place, Stine said. He recommended that people take precautions such as washing their hands frequently and covering their coughs.

“Don’t go to the fair if you’re sick. And if you come here, do a good job of washing your hands and do it frequently. And if you’re going to cough, cover your cough because we don’t always know when we’re going to become ill,” Stine said.

Minnesota has seen 263 swine flu cases resulting in hospitalization so far, he said. The median age for a hospitalized patient has been 12 years old.