State health officials said Thursday the E. coli outbreak is growing, with 13 people sickened in Cleveland, Gaston and Lincoln counties.

Authorities say all of those sickened attended the Cleveland County Fair.

Several of the victims were treated and released from hospitals. But 12-year-old Jordan McNair of Gaston County is hospitalized in Charlotte in intensive care.

State Health Director Laura Gerald of the N.C. Department of Health and Human Services said Thursday that at least two of the victims have E. coli 0157:H7 infections. Those are caused from bacteria found in feces of animals such as cattle, sheep and goats.

Gerald said if people touch contaminated material – such as food or animals – they can transfer the bacteria from their hands to their mouths, or even to other people.

The number of cases has grown dramatically in the past 24 hours. Four people were reported sickened late Wednesday, but the number of cases has increased as local and state officials alert the public to the danger.

State authorities say eight children and five adults are known to have been sickened in the outbreak. Eight victims were from Cleveland County, four from Gaston County, and one from Lincoln County.

Cleveland County Fair director Calvin Hastings said his organization tried to prevent any E. coli problems before the event started.

“We’re required by state law to have five hand-washing stations, and we had nine,” Hastings said. “We borrowed some from the Mountain State Fair. And we had signs posted all around the grounds, reminding people to wash their hands.”

Hastings said Cleveland County Health Department officials worked with food vendors in advance to prevent problems.

“We’re working with health officials on all of this,” he said.

Gerald said state officials are urging the public to be aware of the symptoms. “We are working with county health departments, hospitals and physicians in the region to identify any additional cases,” she said.

Family members of Jordan McNair said he attended the Cleveland County Fair on Sept. 30. He became sick a few days later and was hospitalized late last week. They told reporters he is heavily sedated to help him deal with stomach pain that can accompany the illness.

Officials say it sometimes can take several days for the symptoms to appear.

Those symptoms are largely gastrointestinal – vomiting, diarrhea and stomach cramps. Victims also often run low-grade fevers, usually less than 101 degrees Fahrenheit. Most victims recover in five to seven days, but the illness can be life-threatening for some.

“In some cases in young children,” Gerald said, “this infection can lead to serious complications. So parents should not send sick children to day care or to school, to avoid passing it on to others.”

More than two dozen people were sickened with E. coli last year at the North Carolina State Fair in Raleigh, and the illness was traced to a livestock barn. Among those left seriously ill was a 2-year-old boy from Shelby.

Officials say they have made a number of changes for this year’s fair, which opened Thursday, to prevent a repeat occurrence. The changes are designed to limit contact between fair-goers and animals – and to increase the distance between livestock and food vendors.