A 28-state Listeria outbreak is over, with the sad distinction of being the most deadly outbreak of foodborne illness in the United States in 100 years.

In the end, one out of every five of the victims died from the Listeria contamination spread by a locally grown but widely distributed variety of cantaloupes from Colorado. Thirty of 146 persons infected did not survive. A miscarriage suffered by an Iowa woman was also blamed on outbreak-related listeriosis. 

It was Aug. 29 when the Colorado Department of Public Health and Environment (CDPHE) received the first report of a Listeria infection. More reports followed, and Colorado notified the federal Centers for Disease Control and Prevention (CDC) on Sept. 2 about the growing cluster of  illnesses.

Just four days later, the Colorado cases were linked to others in Nebraska and Texas through PulseNet, the national surveillance system of foodborne pathogens, and that same day,  Sept. 8, “Rocky Ford” cantaloupes from Colorado’s Arkansas River Valley were identified by CDPHE investigators as the food the victims had in common.

CDC joined the multistate investigation the next day and on the following Monday, Sept. 12, the CDPHE warned the public not to eat any “Rocky Ford” cantaloupes grown only in the Centennial State.

On that same Monday, CDC issued its first report on the outbreak, noting 15 illnesses reported in four states. Two days later, CDC said there were two deaths in the outbreak that had quickly expanded to 22 illnesses in seven states.

The news of the first fatalities coincided with Jensen Farms recalling all the Rocky Ford-brand cantaloupes it had shipped for the season — at least 1.5 million melons.

No other Rocky Ford cantaloupes from other Colorado growers were ever implicated in the outbreak. CDC’s final report says only two other produce outlets, Kansas-based Carol’s Cuts and New York-based Fruit Fresh Up, recalled product. Those companies had purchased whole cantaloupes from Jensen Farms and cut them up for retail sale.

“Available evidence indicates that this outbreak is over,” stated the CDC’s final report, issued Thursday.

Colorado, where the popular cantaloupe brand is grown, suffered the most fatalities. Here is the CDC’s final outbreak toll, by state:

– Alabama:  1 case

– Arkansas:  1 case

– California: 4 cases

– Colorado:  40 cases, 8 deaths

– Idaho:  2 cases

– Illinois: 4 cases

– Indiana: 3 cases, 1 death

– Iowa: 1 case

– Kansas: 11 cases, 3 deaths

– Louisiana: 2 cases, 2 deaths 

– Maryland: 1 case, 1 death

– Missouri: 7 cases, 3 deaths

– Montana: 1 case

– Nebraska: 6 cases, 1 death

– Nevada: 1 case 

– New Mexico: 15 cases, 5 deaths

– New York: 2 cases, 2 deaths 

– North Dakota: 2 cases 

– Oklahoma: 12 cases, 1 death

– Oregon: 1 case

– Pennsylvania: 1 case

– South Dakota: 1 case

– Texas: 18 cases, 2 deaths

– Utah: 1 case

– Virginia: 1 case

– West Virginia: 1 case

– Wisconsin: 2 cases

– Wyoming: 4 cases, 1 death

According to the CDC, those who died ranged in age from 48 to 96 years.  The median age was 82.5.

In addition to the one miscarriage, CDC said seven other outbreak cases of listeriosis involved pregnancy.  Four pregnant women were infected and three newborns were diagnosed with listeriosis.

The CDC said virtually all those who became ill were so sick they had to hospitalized. The agency had information on 144 victims, and 99 percent of them were known to have required hospitalization.

The onset of illnesses was from July 31 to Oct. 27. A majority of the victims, 58 percent, were females.  Ages ranged from less than one year to 96 years.  Median age of the victims was 77 years old.

Among the 140 victims who provided information on what they ate before they became ill, 131, or 94 percent, mentioned the suspect cantaloupe.

The U.S. Food and Drug Administration (FDA) previously reported that its investigation found Listeria contamination on both cantaloupes and equipment at the Jensen Farms packing facility in Granada, CO.

Jensen Farms, Frontera Produce USA, and Primus Labs face lawsuits brought by outbreak victims. Frontera distributed the Rocky Ford cantaloupes from Jensen Farms in at least 24 states. Primus Labs was the third-party auditor Jensen Farms used to get a clean bill of health to get its product distributed.

To find a more deadly outbreak of foodborne illness than this 30-death tragedy, one has go back to 1911 when contaminated raw milk killed 48 in Boston.

CDC outbreak map:

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