E. coli O157:H7 related illnesses resulted from contact with petting zoo animals at three separate fairs in Florida, including the Central Florida Fair and the Florida Strawberry Festival, in 2005. AgVenture Farms was a common vendor for the three fairs. The owner of the petting zoo was contacted, and the animals were placed under quarantine for the duration of the investigation. An environmental investigation was undertaken at the fair grounds and the AgVenture Farm. Soil samples and environmental swabs were obtained from the petting zoo exhibit areas of the fairs. E. coli O157:H7 with matching pulsed-field gel electrophoresis (PFGE) patterns was recovered from the animal exhibit areas of the fairs and from six animals from AgVenture Farms.