The outbreak of listeriosis linked to whole Rocky Ford-brand cantaloupes from Colorado’s Jensen Farms is now more than six times larger than it was when the first public warnings about contaminated melons were issued just three weeks ago.

In its eighth update on the rapidly expanding outbreak, the Centers for Disease Control and Prevention (CDC) in Atlanta said 100 people from 20 states have been confirmed infected with one or more of the four outbreak associated strains of Listeria monocytogenes.

Eighteen deaths are now attributed to the outbreak.

Two more deaths in Colorado and one in Kansas were the additional fatalities since CDC’s last update on Sept. 29, when 15 deaths were reported. Arkansas reported its first case linked to the outbreak.

The listeriosis outbreak is responsible for five deaths each in Colorado and New Mexico and two each in Kansas and Texas. States with one death each are Maryland, Missouri, Nebraska and Oklahoma.

More Listeria-connected deaths are likely and may well have already occurred. CDC’s update is good through 11 a.m. Oct. 3. Media reports say there have been other deaths that are not yet included in the CDC totals. 

For example,  Louisiana’s Department of Health and Hospitals is investigating the death of an 87-year-old Baton Rouge woman whose death was caused by a Listeria infection to see if it is connected to the outbreak strains. A similar death is under investigation in Wyoming.

While the outbreak may not have yet reached its zenith, CDC’s profiling of the victims is telling a story. Listeria poises the greatest threat to the elderly, pregnant women and those with compromised immune systems.

CDC’s data shows that illnesses began on or after July 31 and involved people from 35 to 96 years old, with a median age of 79.  Most are over age 60. For the 93 people that CDC has information on, 98 percent have required hospitalization.

Forty-nine percent of the victims are women, including two who are pregnant.  Listeria can cause miscarriage or stillbirths in pregnant women. CDC says “the outcome of each pregnancy is being monitored.”

According to the nation’s top disease agency, individuals who were infected since Sept. 7 are probably not yet included in the data because of the time it takes between someone becoming ill and when the illness is reported.

Cantaloupes are clearly at the center of the outbreak. CDC says of 77 ill persons the agency has sufficient information about, 71 — 92 percent — reported eating cantaloupe in the month before they were infected.

“Several ill persons remembered the type of cantaloupe they had eaten and said they were Rocky Ford cantaloupes, which are grown in the Rocky Ford region of southeastern Colorado.” CDC reported.

This is the first time that cantaloupes have been the source of a Listeria outbreak.  CDC says it rare that any produce is a Listeria carrier.  Usually Listeria outbreaks are caused by deli meats, hot dogs and Mexican-style soft cheeses.

But, produce has some history with Listeria contamination. Sprouts spred Listeria in a 2009 outbreak and celery did so in 2010.

“It’s the very first time we’ve seen listeria contamination in whole cantaloupes,”  Food and Drug Administration (FDA) Commissioner Margaret Hamburg said Tuesday.  “And we’re continuing to work on the root cause analysis to determine how this happened .. .and to find ways to prevent this from happening in the future.  We also intend to take the lessons learned from that outbreak and share them with our partners in industry to reduce the likelihood of future incidents.”

“And just last week, as part of an FDA assignment to determine the prevalence of Listeria in leafy greens, we detected listeria in bagged, chopped Romaine from a ranch in Watsonville, California,” the Commissioner added.  “This resulted in the prompt removal of contaminated products from the market, and may have prevented serious illnesses.  FDA and the State of California have initiated a farm investigation at the implicated ranch, and are conducting environmental sampling at the processing facility, in an attempt to identify what contributed to the positive sample result.”

According to CDC, the U.S. sees about 800 laboratory-confirmed causes of Listeria infection yearly with three or four outbreaks that are typically much smaller than this one.

Three weeks ago, Jensen Farms recalled the 1.5 million cantaloupes that it shipped between July 29 and Sept. 10 to at least 28 states  — Arkansas, Arizona, California, Colorado, Idaho, Illinois, Indiana, Kansas, Louisiana, Minnesota, Missouri, Montana, Nebraska, New Jersey, New Mexico, New York, North Carolina, North Dakota, Ohio, Oklahoma, Pennsylvania, South Dakota, Tennessee, Texas, Utah, Virginia, Wisconsin and Wyoming — with possible further distribution.

Equipment and cantaloupes at Jensen’s packing facility in Granada, CO and cantaloupes collected from grocery stores and the homes of victims all tested positive for L. monocytogenes outbreak strains.

CDC Outbreak Map:


CDC Epi Curve Chart:


  • It’s amazing how fast these food warnings expand in scope. When food warnings come up for a particular food, it’s best to stay away from it completely for a week or so. No matter how small the warnings start off, they almost always grow.

  • Marybell

    People need to take responsibility and clean the vegetables throughly. But seems people have thrown respnsibility to the way side and sue if you get sick. What a shame.

  • Ben Mark

    Maybell, please explain to all of us how to clean a cantaloupe melon or cut lettuce from salmonella or listeria. I’m really interested in your procedure and it will help millions of readers.

  • Stephanie

    You cannot clean Lysteria from a cantaloupe, especially if it’s in the whole cantaloupe. Some bacteria that causes foodborne illness is not able to be removed by washing or even by cooking, because it is resistant!

  • Shelly

    I agree that there are cases of things where people jump to sue, but this is not one…

  • Nancy

    Blaming consumers is a page right out of the food industry’s playbook. Perhaps the Listeria victims did try to wash their cantaloupes, which by that time may have already spread bacteria to other foods in the shopping bag, the kitchen counter, the refrigerator or a fruit bowl. Washing the cantaloupe could have splashed Listeria-laden water all over the kitchen. Or maybe the Listeria was already inside the cantaloupe from a bruise or cut on the rind. If we’re going to have to be responsible for foods that are biohazards, perhaps they should carry warning labels. The problem isn’t that people aren’t thoroughly washing their vegetables or thoroughly cooking their meat. The problem is that the food is contaminated.

  • Brunhilde Merker

    Nancy made a common sense comment. The problem we see here at ScoringAg is, there is no traceback system in place that can find contaminated products in the whole supply chain up to the consumer’s kitchen and be removed within hours instead of weeks. The whole industry is talking about food safety, now even blaming the consumer instead of implementing an effective and affordable traceback system that points to the spot in a field, or every place in the supply chain where each handler’s possible contamination may have occured.