Ice cream cups are recalled due to possible listeria outbreak. Here's what you need to know.

Listeria seen microscopically
Listeria has been linked to ice cream.

It may be perfect ice cream weather, but the Centers for Disease Control and Prevention wants you to check your freezer before you reach for this icy treat. On Aug. 9, Brooklyn, N.Y.-based Real Kosher Ice Cream recalled all flavors of its Soft Serve on the Go ice cream cups due to a potential listeria outbreak.

According to the CDC, “Listeria was found in a ‘Soft Serve On The Go’ ice cream cup collected from a sick person’s freezer, and laboratory scientists are working to determine if it is the outbreak strain of listeria.”

Why is listeria a concern? Here’s what you need to know.

What is listeria?

Listeria refers to the disease caused by a species of bacteria called Listeria monocytogenes. Unlike many other bacteria found in food that can cause illness, this bacteria thrives in the cold, making it especially problematic.

“Listeria has the unfortunate property to grow under refrigeration temperatures, which is uncommon of foodborne illness,” Dr. Albert Shaw, an infectious diseases specialist and professor of medicine at Yale School of Medicine, previously told Yahoo Life. “It can contaminate any food, really, but we see outbreaks in raw fruits and vegetables, as well as improperly heated hot dogs and things like deli meats. Unpasteurized milk or soft cheeses, especially Brie and queso that are made with potentially unpasteurized ingredients, have been associated with outbreaks in the past.”

What are the symptoms?

Mild symptoms of listeria include:

  • Fever

  • Muscle aches

  • Nausea

  • Vomiting

  • Diarrhea

More severe symptoms include:

  • Headache

  • Stiff neck

  • Confusion

  • Loss of balance

  • Convulsions

While listeria can be treated at home, it’s important to seek medical attention if your symptoms worsen. Antibiotics may also be prescribed.

Who should be concerned?

If you ate any of the recalled items, you should monitor your symptoms and seek medical attention.

Dr. Julie Parsonnet, a professor of infectious diseases at Stanford School of Medicine, previously told Yahoo that “pregnant women are at risk because the bacteria can get into the bloodstream and the placenta, and there’s a high risk of fetal loss due to the infection.”

In addition: “The elderly can also get listeria in their blood and their brain, causing meningitis. It’s not a common cause of disease, but among the foodborne illnesses, listeria is one of the more common causes of death.”