The affected product is sold as Infinite Herbs brand organic basil, which comes in 2.5-ounce clamshell-style containers.

The Centers For Disease Control and Prevention says an outbreak of salmonella has been traced to a brand of organic basil sold at Trader Joe's stores.

The affected product is sold as Infinite Herbs brand organic basil, which comes in 2.5-ounce clamshell-style containers.

Seven people who later became sick are thought to have purchased the basil from Trader Joe's.

Overall, the CDC says the salmonella outbreak has caused 17 separate illnesses and put one person in the hospital.

The affected basil was sold at Trader Joe's locations in 29 states and in Washington, D.C. The chain has removed the product from its offerings.

Infinite Herbs, the company that provided the crop, is expected to make a voluntary recall of affected products.

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The CDC urges consumers not to eat any basil that may be contaminated. It says they should discard or return the product to Trader Joe's stores, wash potentially contaminated surfaces with hot soap and water and contact health care providers if symptoms of salmonella illness appear.

Salmonella can cause diarrhea, fever and stomach cramps in humans. Severe infection may also cause vomiting and symptoms of dehydration, and may put the very young or very old at risk of significant illness that requires hospitalization.

Symptoms typically appear between six hours and six days after eating contaminated foods. Most people recover within a week without special treatment.