Residents of five Colorado counties are now among the 21 people sickened with Salmonella in an outbreak. All of them ate food from Burrito Delight restaurants.

The number of laboratory-confirmed cases more than doubled during the weekend, following the initial announcement of eight people having been sickened by the foodborne pathogen.

According to the Weld County Department of Public Health and Environment, Burrito Delight restaurants in Fort Lupton and Dacono, CO, are the source of the outbreak. The investigators continues to work to pin down the exact food source that’s responsible.

Weld County officials closed both Burrito Delight restaurants on Feb. 22. They remain closed pending the completion of the investigation. The two burrito outlets must meet specific conditions before they will be allowed to serve customers again.

The Fort Lupton restaurant racked up 22 red violations during five inspections since late 2015. Red violations are those “more likely than other violations to contribute to food contamination or illness.”

Inspectors found 20 red violations at the Dacono Burrito Delight during the past two years. Weld County rated both restaurants as  “marginal,” meaning they were allowed to correct their red violations on the spot and remain open.

Subsequent inspections, however, found repeat violations for such fundamental restaurant practices as keeping hot food hot and cold food cold.

Confirmed cases as of Monday, by county,  included in 14 Weld, 3 in Larimer, 2 in Boulder, 1 in Morgan, and 1 in Adams. Four of the 21 required hospitalization.

Burrito Delight in Fort Lupton, located about 30 miles north of Denver, is linked to 20 cases. The Dacono outlet is responsible for one illness.

Public health investigators traced all of the Salmonella infections to Burrito Delight. Nine of the sick people either dined in at the Fort Lupton restaurant or were take-out customers who returned to their place of employment. The other 12 attended one of two Aims Community College events that Burrito Delight catered on Feb. 6 and 12.

The college maintains a two-building satellite campus in Fort Lupton.

Weld County officials expect the number of cases associated with the outbreak to continue to rise. They say the investigation into the Salmonella illnesses now involves several locations in Weld County.

“The investigation continues around possible food sources,” county health officials said in their Monday update. They continue to stress that the public is not currently at risk from the two restaurants, which will remain closed for the duration of the investigation.

Officials are asking that anyone in Northern Colorado who became sick with Salmonella in February to call the Weld County Health Department Salmonella triage line at 970-400-2374. Staff will answer during regular business hours. After hours and on weekends, callers may leave a message.

Symptoms of Salmonella illness include diarrhea, upset stomach, fever, and occasionally vomiting.

Anyone who suspects they became ill should contact their healthcare provider. For some people, diarrhea may become so severe that they require hospitalization. Symptoms typically appear 6-72 hours after eating contaminated food. People are usually sick for 4 to 7 days without treatment. However, in severe cases, the symptoms may last longer or result in serious complications

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