CHICAGO (CBS) — So far, Illinois has seen only one confirmed case of listeriosis from tainted cantaloupe, but cases could be showing up well past Halloween.

As WBBM Newsradio’s Nancy Harty reports, an 82-year-old suburban Cook County woman was hospitalized with listeriosis earlier this month. She was treated and released.

LISTEN: WBBM Newsradio’s Nancy Harty reports

More cases could be coming, since the incubation period has a huge range.

The bacterium is linked to cantaloupes from the Rocky Ford growing region in southern Colorado, which have been sold across the country.

Infectious Disease Expert at North Shore University Health System Dr. Becky Miller explains how a person can contract listeriosis within six hours, or 90 days.

“Most of the time, people are finding out right away. There’s nothing you can really do to prevent from getting sick if you’ve already been exposed, like you can’t take any medication,” she said.

Miller says the incubation period is a combination of how much you’re exposed to and the state of your health.

She says the very young, very old, pregnant woman and those with existing health conditions are at greatest risk.

Listeriosis is caused by the bacterium Listeria monocytogenes. Symptoms include fever, nausea, vomiting and diarrhea.

The Centers for Disease Control and Prevention says the cantaloupes are known were grown on the Jensen Farms in Granada, Colo.

The company has voluntarily recalled the cantaloupes, which were shipped from the Rocky Ford growing region of southern Colorado between July 29 and September 10, according to the Food and Drug Administration.

Affected cantaloupes may be labeled “Colorado Grown, Distributed by Frontera Produce, USA, Pesticide Free,, Sweet Rocky Fords” but not all recalled cantaloupes are labeled with a sticker, according to the FDA.

Consumers are urged to throw out the cantaloupes in a sealed container so that children, animals and wildlife can’t eat them, according to the FDA.

The Sun-Times Media Wire contributed to this report.

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