Experts: Source Of Blue Bell Listeria Contamination Tricky To Locate

People in Broken Arrow are standing behind the Blue Bell plant. Folks stopped by the chamber office Thursday to sign a "Broken Arrow Loves Blue Bell" banner.

The BA plant shut down last week after some flavors of ice cream made there tested positive for Listeria.

If you want to sign the banner, it will be at the Central Park Community Center Thursday night and back at the BA Chamber office during the day Friday.

City leaders plan to hang it at the Blue Bell plant Friday evening.

With the recall in Broken Arrow, and others around the country involving Listeria, we wanted to know what it is and how it gets into the manufacturing process.

Production at the Blue Bell plant in Broken Arrow is shut down due to the contamination, and experts said Listeria is very tricky, because it's a type of bacteria that could come from anywhere.

Ice cream containers fill dumpsters outside the Blue Bell plant in Broken Arrow.

4/3/2015 Related Story: Blue Bell Suspends Broken Arrow Operations After Contamination Found

The company has now recalled at least seven flavors after being contaminated with Listeria, causing illnesses and even deaths in Kansas and Texas.

Another food maker, Sabra Dipping Company, has recalled its classic hummus due to a Listeria contamination.

But what is Listeria?

Epidemiologist Nicole Schlaefli with the Tulsa County Health Department said it's a common bacterium that can be deadly to certain people.

"The symptoms are more likely to appear in people who have lowered immune systems, so that's going to go to that little sub population of very young, very old and somehow someone having something wrong with their immune system, like someone who is pregnant, someone on Chemo, on radiation, something along those lines," Schlaefli said.

She said it's a common bacterium that most of us come into contact with every day, which makes finding the source of the contamination difficult.

"Leaf litter, you can get it from working in your garden. It's very common in general, several animals will carry it and deposit it in their feces and things like that," Schlaefli said.

She said, "It could have been on the products coming into the plant, it could have been from the person fixing the machinery, it could have been that, maybe the plant had stray animals come and slipped through one day or something and they had Listeria. There are a lot of possible ways things could have gotten infected."

So how do companies clean up the mess? Schlaefli said a recall is a good place to start.

"Like we're seeing with the Blue Bell plant, they're recalling items that were made on lines that they know were affected," she said.

They said they recommend, after a recall, a thorough cleaning before reopening.

Listeria symptoms are much like food poisoning - nausea, diarrhea, vomiting and fever.