Health investigators are racing to identify the brands of caramel apples suspected of being tainted with Listeria monocytogenes and causing a deadly outbreak of listeriosis.
Number of states involved: 10
Cases in California: 1
Recall: 1; Happy Valley brand caramel apples
Symptoms of listeriosis: High fever, headaches, neck stiffness, nausea and diarrhea
At greatest risk: Infants, the elderly, people with weakened immune systems, pregnant women.
Only three deaths have been confirmed as being caused by listeria.
Sources: U.S. Centers for Disease Control and Prevention; California Department of Public Health