(NEXSTAR) – The Centers for Disease Control and Prevention has recorded a “significant” number of new infections amid a multi-state outbreak of salmonella stemming from an unknown food source.

At least 279 infections have been linked to the strain observed in the outbreak, 26 of which have required hospitalization, according to the latest CDC case count made public on Friday. Last week, the CDC had only confirmed 127 infections linked to the unidentified food source, including 18 hospitalizations.

The outbreak has also expanded to a total of 29 states, or four more than when the CDC first reported the infections last week.

No deaths have been linked to the outbreak.

Salmonella Oranienburg, the strain observed in this outbreak, began sickening people on Aug. 3 and grew “rapidly” in the following weeks, according to the CDC. The agency estimates that the actual number of sick people is “likely much higher” than 279, as many infected individuals often recover without seeking treatment or getting tested.

It can also take up to four weeks to determine if a sick person is indeed part of the outbreak, the agency says.

Investigators have yet to determine a food source linked to the outbreak, though the strain has since been identified in a takeout container provided to a restaurant customer, per the CDC’s lab data.

“State and local officials have collected food items from some of the restaurants where sick people ate,” the CDC wrote in Friday’s update. “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.”

The CDC says, however, that it is “not possible” to determine exactly which ingredient or component was contaminated, as the takeout container contained other foods.

Health officials are currently gathering additional data, per the CDC.

In a statement shared with Nexstar days before the CDC’s latest update, the agency said it was continuing to see “a significant number of new cases reported each day.”

The statement, issued by Belsie González, MPH, the senior public affairs specialist for the CDC, added that “it remains important that people report symptoms to their healthcare provider and local health department.”  

Symptoms of salmonella include diarrhea, fever, stomach cramps, and possible nausea, vomiting or headache. Those experiencing more severe symptoms — including dehydration, prolonged vomiting, prolonged diarrhea, or diarrhea with a fever of over 102 degrees F, among other symptoms — should contact a doctor immediately.

A complete list of the number of infections and where they were reported can be found below.

• Texas: 81
• Oklahoma: 40
• Illinois: 23
• Virginia: 22
• Minnesota: 19
• Massachusetts: 10
• Maryland: 9
• Wisconsin: 8
• Arkansas: 7
• Kansas: 6
• New Mexico: 6
• California: 5
• Connecticut: 5
• South Dakota: 5
• Michigan: 4
• Nebraska: 4
• New Jersey: 4
• Pennsylvania: 4
• Missouri: 3
• Florida: 2
• New York: 2
• North Carolina: 2
• Utah: 2
• Indiana: 1
• Iowa: 1
• North Dakota: 1
• Oregon: 1
• South Carolina: 1
• Tennessee: 1

More information on this outbreak and salmonella infection can be found at the CDC’s website.