WASHINGTON (AP) – Federal health officials have raised the death toll to 18 in an outbreak of listeria in cantaloupe.

The Centers for Disease Control and Prevention said Tuesday it has confirmed 100 illnesses in 20 states, including the 18 deaths. The agency said it has confirmed two additional deaths in Colorado and one in Kansas since last week.

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The CDC had previously reported five deaths in New Mexico, three deaths in Colorado, two deaths in Texas and one death each in Kansas, Missouri, Nebraska, Oklahoma and Maryland.

The death toll may continue to rise. Wyoming’s state health department said it has confirmed a death in that state linked to the outbreak, though the CDC did not include that case in its count. CDC officials have said the symptoms of listeria can take up to two months to show up and that they expect more illnesses.

Jensen Farms in Holly, Colo. recalled its cantaloupes Sept. 14 after the farm’s melons were traced to the listeria illnesses. The farm says it shipped cantaloupes to 28 states, though the FDA has said it may be more. Illnesses have been discovered in states that were not on the shipping list and company officials have said the product is often sold and resold, so they do not know everywhere it went.

The outbreak is the deadliest in the United States in more than a decade. Listeria is a rare disease that usually only affects about 800 people a year, according to the CDC. But it is one of the deadliest foodborne pathogens, killing up to one in five people it sickens.

The FDA said state health officials found listeria in cantaloupes taken from Colorado grocery stores and from a victim’s home that were grown at Jensen Farms. Matching strains of the disease were found on equipment and cantaloupe samples at Jensen Farms’ packing facility in Granada, Colo.

FDA Commissioner Margaret Hamburg said Tuesday that the agency is still investigating the cause of the outbreak. Officials have said they are looking at the farm’s water supply and possible animal intrusions among other things in trying to figure out how the cantaloupes became contaminated. Listeria bacteria grow in moist, muddy conditions and are often carried by animals.

Most of the contaminated melons should be out of the food supply by now. The farm last shipped its cantaloupes on Sept. 10, and their shelf life is about two weeks. Officials from the CDC and the Food and Drug Administration say that any cantaloupes not from Jensen Farms are safe to eat.

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The recalled cantaloupes may be labeled “Colorado Grown,” `’Distributed by Frontera Produce,” `’Jensenfarms.com” or “Sweet Rocky Fords.” Not all of the recalled cantaloupes are labeled with a sticker, the FDA said.

Government health officials said this is the first known outbreak of listeria in cantaloupe. Listeria is generally found in processed meats and unpasteurized milk and cheese, though there have been a growing number of outbreaks in produce.

Listeria is more deadly than well-known pathogens like salmonella and E. coli, though those outbreaks generally cause many more illnesses. Twenty-one people died in an outbreak of listeria poisoning in 1998 traced to contaminated hot dogs and possibly deli meats made by Bil Mar Foods, a subsidiary of Sara Lee Corp. Another large listeria outbreak, in 1985, killed 52 people and was linked to Mexican-style soft cheese.

While most healthy adults can consume listeria with no ill effects, it can kill the elderly and those with compromised immune systems. It is also dangerous to pregnant women because it easily passes through to the fetus. The CDC said the median age of those sickened is 79.

Symptoms include fever and muscle aches, often with other gastrointestinal symptoms.

The CDC has reported illnesses in Alabama, Arkansas, California, Colorado, Idaho, Illinois, Indiana, Kansas, Maryland, Missouri, Montana, Nebraska, New Mexico, North Dakota, Oklahoma, Texas, Virginia, West Virginia, Wisconsin, and Wyoming. Colorado has the most illnesses with 30, while Texas has 14 and New Mexico has 13.

– By Mary Clare Jalonick, AP Writer

LINK: Listeria Outbreak Resources

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