A month into an investigation of a Salmonella Oranienburg outbreak investigators have a lead and it’s pointing to cilantro as a possible cause behind the illnesses.

As of Sept 21, there were 279 confirmed patients across 29 states, according to the Centers For Disease and Prevention. The agency first identified the outbreak on Sept 2 when there were 20 sick people.

The source of the outbreak has remained a mystery as more and more people across the country have become infected. Testing has finally found the outbreak strain in a food container.

“The outbreak strain of Salmonella Oranienburg was found in a sample taken from a takeout condiment cup containing cilantro and lime. The sick person reported that the condiment container also contained onions, but none were left in the cup when it was tested,” according to the CDC.

“Because multiple food items were present in the container and in the sample that was tested, it is not possible to know which food item was contaminated. We are using this information in conjunction with other available information to help narrow the list of possible foods linked to illness.”

Illnesses started on dates ranging from Aug. 3 to Sept. 13. Sick people range in age from less than 1 year to 89 years, with a median age of 35, and 59 percent are female. Of 86 people with information available, 26 have been hospitalized and no deaths have been reported.

“The true number of sick people in an outbreak is likely much higher than the number reported, and the outbreak may not be limited to the states with known illnesses. This is because many people recover without medical care and are not tested for Salmonella. In addition, recent illnesses may not yet be reported as it usually takes 3 to 4 weeks to determine if a sick person is part of an outbreak,” according to the CDC.

State and local public health officials are interviewing people about the foods they ate in the week before they got sick. CDC is analyzing the data and has not identified a specific food item as a potential source of this outbreak. 

Several groups of people in “subclusters” at restaurants in multiple states have been identified. These subclusters are groups of people who do not know one another who ate at the same restaurant and got sick. Investigating these subclusters can sometimes help identify a food item eaten by all of the sick people that could be the source of the outbreak.

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