In October 2015 Maine Center for Disease Control and Prevention (ME CDC) staff investigated an outbreak of E. coli O111:H8 infections among two children who attended the Oxford County Fair. One child, age 20 months, attended the fair on September 16 and September 19. The second child attended the fair on September 18. Both children were infected with an indistinguishable strain of E. coli O111 designated as PulseNet Pattern combination EXD01.1540/EXDA26.1144. The twenty month old child died his infection.

Public health investigators identified two potential exposures, consumption of green grapes and attending the Oxford County Fair. Investigators ruled out green grapes as a source of infection after learning the grapes were prepackaged and distributed nationally. E. coli O111 was not found when samples were collected 18 days after the fair had ended and the grounds had been cleaned. It is noteworthy, however, that a different Shiga toxin E. coli, E. coli O100:nonmotile was found in an environmental sample. There was no testing of animals that were exhibited at the Oxford County Fair.