The United States Centers for Disease Control (CDC) warned U.S. citizens to avoid eating pre-packaged, commercially produced caramel apples. This statement came after the health officials linked the apples to a recent outbreak of Listeria.

As of Dec. 18, 28 people have been infected by the bacteria, with 21 hospitalizations and five deaths, the CDC reported. The cases have been reported in 10 states around the continental U.S., ranging from California to North Carolina.

CDC officials are currently working with public health officials across these states, along with the Food and Drug Administration, to investigate the infections. The investigators are working to determine the source of the contamination, as well as the specific brands of caramel apples that can be linked to the outbreak.

There is no correlation between the infections and fresh apples or caramel candies. Homemade caramel apples are still considered safe. If you’re unable to determine if your caramel apples are commercially produced, the CDC advises that you dispose of them.

According to Mayo Clinic, Listeria is a foodborne bacterial illness that often goes unnoticed by the average patient. The bacteria is especially dangerous for pregnant women and people with weakened immune systems. Listeria is commonly contracted from eating improperly processed deli meats and unpasteurized milk products.

The symptoms of Listeria include fever, muscle aches, nausea, and diarrhea. If untreated, the bacteria can spread to the nervous system, causing convulsions, confusion and loss of balance. The CDC advises anyone exhibiting these symptoms after eating a commercially-produced caramel apple to contact their healthcare provider. Prompt antibiotic treatment can help curb the infection.

In their statement, the CDC reported that nine of the 28 reported cases were pregnancy-related, meaning they occurred in pregnant women or newborns. Three of the reported cases in children ages 5-15 coincided with an invasive illness (Meningitis). Of the 18 patients interviewed, 15 reported that they had ingested commercially produced caramel apples.

The full CDC statement is available here.