OXFORD, Maine (CBS/AP) – A little boy has died from E. coli after visiting a county fair in Maine.

Colton Guay was 20 months old.

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His father says Colton had severe diarrhea shortly after visiting a petting zoo at the Oxford County Fair in September.

“It is believed that he contracted it through simple interaction with farm animals at a local fair (based on other similar cases). It began with severe diarrhea and ended with massive brain seizures that ultimately took his life,” his father Jon wrote on Facebook.

“I have learned that there is no pain worse than losing the life of your childs.”

Health officials said another child also contracted E. coli at the fair, but they haven’t definitively linked the illnesses to the petting zoo.

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John A. Martins, the Public Health Information Officer for Maine’s Center for Disease Control told WBZ-TV’s Jim Armstrong that “the Maine CDC has been investigating for any common links to the cases, and that effort continues. ”

“Maine CDC is working with the State Veterinarian and the Department of Agriculture, Conservation and Forestry to investigate the fact that each child attended the Oxford Fair and visited the animal barns and petting zoo.”

Fair President Jackie Young says she’s cooperating with the investigation.

Experts say the best defense against E. coli is to thoroughly wash your hands with soap and water.

Mark Anderson, veterinarian at Maine’s Fryeburg Fair told WGME that “what happened to these poor two toddlers is so rare. I mean, obviously if this was an everyday occurrence or anything even close to that, we wouldn’t even have petting zoos.”

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