CDC recommends that U.S. consumers do not eat any commercially produced, prepackaged caramel apples. From the CDC:
CDC is collaborating with public health officials in several states and with the U.S. Food and Drug Administration (FDA) to investigate an outbreak of Listeria monocytogenes infections (listeriosis) linked to commercially produced, prepackaged caramel apples. Listeria can cause a serious, life-threatening illness. The information CDC has at this time indicates that commercially produced, prepackaged caramel apples may be contaminated with Listeria and may be causing this outbreak.
|Map of Persons infected with the outbreak streains of Listeria monocytogenes, by state of residence, as of 12-18-14.|
For more info: Multistate Outbreak of Listeriosis Linked to Commercially Produced, Prepackaged Caramel Apples.