HOUSTON (KTRK) -- It's a traditional Halloween treat, but a new study shows that some store-bought candy apples could develop Listeria. A recent study revealed how the bacteria may have developed.
It's no doubt, it's a sweet treat adults and children love this time of year. However, a recent study uncovered if you take a bite from the wrong apple, it could be life threatening.
"Seven people died," said Dr. Jay Neal, Food Microbiologist.
Also 35 people got sick last year, and some of those confirmed cases were here in Texas, according to the CDC, after some premade candy apples developed listeria.
"The store-bought ones are the ones really tied to the outbreak last year," said Dr. Neal.
Dr. Neal said the apples are prepped and washed in large tub for a period of time. If there's a bad apple in the mix that contains bacteria, it could spread to other apples.
"But if you're not monitoring the antimicrobial wash in the system that can be a source of cross contamination," said the doctor.
So how does an apple become contaminated with Listeria?
"Let's pretend the knife is my stick. When I cut it I've actually released juice and the bacteria comes in contact with the water," said Dr. Neal.
If a candy apple stays refrigerated there's no problem. Experts believe the bacteria grows when the treats are left out at room temperature for weeks.
"It's something that I have to think about now," said a concerned mother.
After reviewing the study, Kroger pulled all of its unrefrigerated apples off its shelves. Walmart began working with its suppliers to keep the apples at 41 degrees at all times. As for Randall's, they too are keeping theirs refrigerated and tossing them after 7 to 8 days.
If you recently consumed an apple that was not refrigerated, there are symptoms to be aware of.
"Look out for fever, stiff neck, diarrhea (and) not acting normally," said Dr. Helene Sheena, with Kelsey-Seybold Clinic. "I would probably contact their pediatrician."
Your safest bet, doctors suggest, is to make them at home and eat them right away.
Eyewitness News found unrefrigerated caramel apples at a few Target stores. Target did not call us back after numerous attempts to get in touch with them. We are still waiting to hear from them regarding those. null
Grocery stores taking new measure to ensure safety of candy apples