They held a news conference at 9:30 a.m. to announce their findings and reassure the public that they are taking actions to ensure a safe experience fair-goers.
State Epidemiologist Dr. Megan Davies said they were first notified about possible E. coli infections on Oct. 25. A total of 27 people - adults and children - contracted E. coli after attending the fair in October.
Davies said the illness is likely related to animal contact, though the study did not implicate any specific animal or breed in the outbreak.
After an investigation, officials determined that the infections were transmitted in the Kelley Building at the North Carolina State Fair.
The Kelley Building was where sheep, goats, and pigs were housed and competed in livestock shows during the fair.
Officials said no other exhibits, foods or activities were linked to the E. coli infections, including the petting zoo.
They said they are working to identify additional protective measures for fairgoers in the future.
Agriculture Commissioner Steve Troxler said Thursday that they are forming a task force in an effort to make the annual event safer.
"We realize this needs to be a safe place ... our goal is to put on a safe fair," Troxler said.
There was another outbreak linked to the fair in 2004, and since then, officials said they had gone to great lengths to prevent any new ones.