Two more confirmed cases added during the last week brought the number of illnesses in the Colorado Salmonella outbreak to 37.  There have been no new cases for the past five days, and it appears the outbreak has peaked at 37 confirmed laboratory cases, according to the Weld County Health Department.

Linked to the outbreak are two burrito restaurants that catered two community college events in early February. Weld County continues to investigate the incident at multiple locations in the area north of Denver.

The outbreak became known in mid-February when 17 people from the Aims Community College campus in Greeley became sick from food catered by the Burrito Delight restaurant located 40 minutes away in Fort Lupton, CO. An additional 20 patrons became ill after eating food directly from Burrito Delight. It has a second location in Dacono, CO.

The Salmonella outbreak is centered in Weld County with 27 cases. Ten others have residences in five other Northern Colorado counties.

The Burrito Delight restaurants were both listed as “marginal,” or the equivalent of a “D” grade by Weld County’s restaurant inspectors. Both routinely racked up red violations for infractions that threaten public health.

Both restaurants are closed for the duration of the investigation, according to Weld County. Health officials say the public is no longer at risk. Four people have been hospitalized, and there are no deaths linked to this outbreak.

“Several employees from the restaurant have tested positive for Salmonella,” said Mark E. Wallace, MD, MPH, Executive Director of the Weld County Health Department. “But it remains unclear if they or a food source is the illness link. It may be a challenge to find the definitive answer.”

The Health Department is partnering with the Colorado Department of Public Health and Environment in examining all possible sources of the illness. Large outbreaks are complicated, and it becomes difficult to isolate the index case of exposure, said Wallace.

Salmonella is a bacterium that causes symptoms like diarrhea, upset stomach, fever, and occasionally vomiting. Symptoms typically appear 6-72 hours after eating contaminated food and usually last 4 to 7 days without treatment. In severe cases, the symptoms may last longer, but most people recover on their own. Anyone who continues to suffer symptoms of Salmonella should contact their healthcare provider. For some people, diarrhea may become so severe they require hospitalization.