Colorado public health officials have ruled out waterborne, airborne and person-to-person infection routes for an outbreak of illnesses among several dozen attendees of a rodeo, leaving food as a likely source.

Garfield County Fairgrounds ColoradoThe Garfield County Public Health Department repeated its plea Friday for help from everyone who attended the rodeo in Rifle, CO, at the county fairgrounds on Monday, June 5. About 200 people were at the Rifle Rodeo, according to the health department.

“It appears that people became ill approximately six hours following the end of the rodeo event Monday night,” Billy Harkins, county environmental health specialist, said in the pubic health alert.

“We are still investigating the cause of the outbreak, and are taking all possible factors into consideration. The total number of individuals who became ill and the duration of their illness has not been confirmed.”

Those who reported their illnesses helped investigators narrow possible causes significantly already. County officials reported Friday that the dozens of illnesses did not develop from a waterborne or airborne source and were not transferred by person-to-person contact.

The quick onset of symptoms ruled out those sources, as well as some specific pathogens. The common foodborne pathogens E. coli, Salmonella and Hepatitis A take longer after exposure to produce symptoms, according to the Garfield County alert update.

“Samples have, and are being sent to a state lab for testing. Public health staff hopes to receive data next week, but this depends on the number of investigations of both ill and well people that staff is still in the process of conducting,” according to the update.

“June 5 Rifle Rodeo attendees are asked to call 970-625-5200, Ext. 8128, and a public health representative will return the call to complete a brief questionnaire that will help to track down the source of the outbreak.”

The cooperation of rodeo attendees who did not become ill will help investigators rule out food sources because they will be able to compare foods eaten by outbreak victims with foods eaten by those who did not get sick.

So far symptoms reported by outbreak victims include nausea, cramping and diarrhea.

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