The boy was among four documented cases of children ages 2 to 13 picking up the bacteria at the fair, the county said in a statement Friday. The exposure was "linked to contact with animals," possibly at the fair's petting zoo, according to the statement.
The other three children infected were not hospitalized, the county said, and have recovered. The boy died from complications of the disease on June 24.
"Our sympathies go out to the family of the child that died from this illness," said county public health officer Wilma J. Wooten. "While most people recover from this illness without complications, 5 to 10 percent of people diagnosed with STEC [Shinga toxin-producing E. coli] develop the life-threatening kidney infection."
Four cases of E.coli bacteria linked to San Diego County Fair. pic.twitter.com/0zRZTNgU5l— SD HHSA (@SDCountyHHSA) June 29, 2019
Officials urged anyone potentially showing symptoms, which include stomach cramps, diarrhea and vomiting, to contact a doctor.
They also recommended making sure to wash your hands after any contact with animals.