GREELEY, Colo. (CBS4) – Concerns about a salmonella outbreak in processed chicken have prompted King Soopers grocery stores on the Front Range to take a brand off its shelves.

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“It’s a worry, and it seems like it’s happening quite frequently lately,” said Greeley mother Lori Johnstone.

The poultry contaminated with salmonella was packaged by Foster Farms and it was processed in three plants in California. Health officials with the USDA have given an ultimatum to the company that the factories must be shut down if the plants aren’t cleaned up.

Three hundred people have gotten sick in 18 states since March. Four people to date have gotten sick in Colorado from the chicken.

Lori Johnstone

Lori Johnstone speaks with CBS4’s Tom Mustin. (credit: CBS)

Johnstone is one of many shoppers who told CBS4 she’s concerned about the outbreak.

“As a mother you worry about your children all the time, and this specifically is a big scare for a mother,” she said. “I have it in my freezer right now so that worries me quite a bit. I’m going to go home and check it out.”

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The people who got sick were residents of Weld, Pitkin, Adams and Delta counties.

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Weld County Health Department spokesman Eric Aakko said salmonella symptoms include fever, cramps, vomiting, and abdominal pain.

He says there are ways to combat the problem.

“Always wash your hands with soap and warm water, keep your food in the fridge until you’re ready to cook it and if you’re cooking poultry — and because we’re talking about salmonella — make sure the internal temperature reaches at least 165 degrees,” he said.

The tainted packages of chicken have code numbers p6137, p6137a and p7632. If you have purchased one of the tainted batches of chicken at King Soopers, the store says you can bring it back into their stores for a full refund.

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“Salmonella is one of the most common sources of food poisoning in the U.S.,” Aakko said.