Kent Phillips / wdwnews.com

Several dozen people apparently were sickened after visiting Walt Disney World's 'Wild Africa Trek' attraction at the Florida theme park. Health officials are investigating the outbreak.

Several dozen people have been sickened by a mystery illness linked to visits to the “Wild Africa Trek” tour offered by Walt Disney World in Buena Vista, Fla., local health officials said Thursday.

“Hundreds” of people have been questioned so far in connection with the cluster of flu-like illnesses detected in early June, said Dain Weister, a spokesman for the Orange County, Fla., Health Department.

Visitors who took the three-hour boutique tour -- which includes nature hikes, crossing a rickety foot bridge, sightings of giraffes, hippos and other animals and a catered snack on a manmade savannah -- came down with symptoms including diarrhea, abdominal pain, fatigue and nausea, Weister said.

“The thing we’re trying to get everyone to understand is this is some kind of stomach bug,” said Weister, noting that no specific pathogen has been identified.

Though the symptoms may resemble those associated with infections such as norovirus, that bug usually causes more vomiting than victims reported, Weister said.

Most of the illnesses occurred during two days in early June, he said, adding that he didn't know the exact dates. No one has been hospitalized. Victims ranged from children to adults, including entire families.

Health department officials learned of the outbreak on June 11. Inspectors immediately reviewed Disney's food service operations -- and found no concerns, Weister said. Disney officials have conducted a thorough environmental cleaning, added more hand sanitizers and reiterated hand hygiene instructions for employees.

“We are working closely with the Orange County Health Department to review the situation,” said Disney spokeswoman Andrea Finger.

The Wild Africa Trek is offered several times each day at Disney’s Animal Kingdom, part of the Florida theme park. Groups of no more than 12 “trekkers” travel through areas of the Harambe Wildlife Reserve that aren’t available to usual visitors. Guests pay $139 to $249 a person for the tour, on top of regular admission, according to a report in the Orlando Sentinel newspaper.

The Animal Kingdom theme park attracts some 9.8 million visitors each year.

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