State and county health officials have concluded the petting zoo at the Cleveland Co. Fair is the cause of E. coli outbreak across the North Carolina region in late September.

WBTV reports that “N.C. Department of Health and Human Services have determined that the petting zoo at the Cleveland County Fair was the initial source of exposure to E. coli,” the statement released on Friday said.

More than 100 people were infected from the bacteria and a 2-year-old died as a result of the infection that spread into neighboring counties in the early weeks of October. 

According to test results, weather may be one of the factors that played a role in widespread contamination of the area surrounding the petting zoo exhibit.

Two specific strains of E. coli on cases from the outbreak were matched to environmental samples taken from fair grounds. Heavy rains during the run of the fair, from 9/29 to 10/8 resulted in runoff that may have spread contamination from petting zoo into nearby areas.

So why didn’t anyone predict the potential problem when the rain was coming down?