Food Poisoning Health Center

Dirty Equipment Likely Led to Listeria Outbreak

Testing of Samples continued...

"Because of the long incubation period of listeria -- that's the time between when the person is exposed and when they get ill -- it's too soon to declare the outbreak over," Mahon says, "We'll need to monitor for at least another two weeks."

The rapid investigation and cooperation between state and federal officials was credited for preventing more cases and deaths.

A consumer alert about cantaloupes was issued within 10 days after the outbreak was first reported to federal officials.

"Listeria outbreak investigations can often take a month or longer, so this is a real success," Mahon says.

FDA officials say the investigation into how the contamination happened will continue so that future outbreaks can be prevented.

FDA Commissioner Margaret Hamburg, MD, says that though the response to the outbreak was "quick and effective," there are still many lessons yet to be learned.

"The tragic deaths and illnesses from this outbreak have again demonstrated the need to continually address and improve the food safety system," Hamburg says.