Listeria can cause fever, neck stiffness, confusion and vomiting, according to the CDC. The elderly and those with weakened immune systems are at a greater risk of developing serious symptoms. Listeria is especially dangerous during pregnancy and can infect the newborn or lead to premature delivery.
The CDC and FDA have urged consumers to ask their local retailers whether or not their cantaloupes came from Jensen Farms, cautioning, "if you're in doubt, throw it out."
At this point, all of the Jensen Farms cantaloupes should have been pulled from retailers' shelves. And the shelf life of cantaloupes is relatively short so most of the infected cantaloupes are now no longer palatable.
Even so, the number of illnesses may continue to rise.
"The incubation period for listeria is on average one to three weeks, and can be as much as two months or more," Dr. Thomas Frieden, director of the CDC. "So unfortunately there is continued risk from product that's already out there. For that reason, check the label."
The FDA asks consumers to follow these safety tips to help prevent illness:
Wash hands with warm water and soap for at least 20 seconds before and after handling food.
Wash the inside walls and shelves of the refrigerator, cutting boards and countertops; then sanitize them with a solution of one tablespoon of chlorine bleach to one gallon of hot water; dry with a clean cloth or paper towel that has not been previously used.
Wipe up spills in the refrigerator immediately and clean the refrigerator regularly.
Always wash hands with warm water and soap following the cleaning and sanitization process.