The FDA has opened a new investigation into a Listeria monocytogenes outbreak linked to a food it has not yet identified, and the case count in a separate E. coli O157:H7 outbreak has climbed from 25 to 38. Both updates appeared in the agency's outbreak investigation table on Sept. 30.
The new Listeria outbreak, reference number 1415, includes 11 cases. It is now the third active Listeria investigation on the table in which the source food has not been named. FDA has begun traceback, but no recall has been announced.
The same update also added an E. coli O26:H11 outbreak linked to raw milk cheese that had already been recalled. For the outbreaks with no named food, there is no specific product to avoid yet, only general precautions. But the updates are a reason for people at higher risk of Listeria and E. coli complications to be careful with foods known to carry these germs.
New Entries on FDA's Outbreak Table
"A new outbreak of Listeria monocytogenes (ref #1415) linked to a not yet identified product has been added to the table. FDA has initiated traceback," the agency wrote.
The E. coli O157:H7 outbreak, reference number 1421, was first posted Sept. 23. It is listed alongside a U.S. Department of Agriculture reference number, which suggests the two agencies are working together. "For the outbreak of E. coli O157:H7 (ref #1421), the case count has increased from 25 to 38. FDA has initiated sample collection," the update said.
The other two unnamed-source Listeria investigations also grew. Outbreak 1417, posted Sept. 23, rose from 40 to 44 cases. Outbreak 1379, posted in July, rose from 10 to 11 cases and has reached the on-site inspection and sampling stages.
MedicalDaily previously reported on the two new Listeria and E. coli outbreaks when they first appeared, at 40 and 25 cases. Since then, a new Listeria investigation has opened, and the E. coli outbreak has grown by 52%.
Traceback Explained
FDA describes traceback as "the examination of how certain products moved through the supply chain from the end consumer all the way back to the farm or manufacturer," according to its CORE Network page.
In practice, investigators compare what sick people ate with store and distributor records. If several patients bought the same food from different places, records can point back to a shared supplier. Sample collection, the stage now underway in the E. coli outbreak, means testing food or environmental samples for the outbreak strain.
FDA does not name a food until it has enough evidence. The agency "will not publicly name a specific product until there is sufficient evidence to implicate that product as a cause of illnesses or adverse events," its table explains. For the new Listeria outbreak, FDA has not released where patients live or their ages, Food Safety News noted.
The table does not list hospitalizations, deaths, or states for these four outbreaks. FDA has not said whether the three Listeria investigations are connected.
Precautions for Higher-Risk Households
Listeria is most dangerous for pregnant women, newborns, adults 65 and older, and people with weakened immune systems. It can cause miscarriage or stillbirth, and serious illness usually begins within two weeks of exposure. Symptoms include fever, muscle aches, headache, stiff neck, confusion, loss of balance, and seizures.
E. coli O157:H7 commonly causes severe stomach cramps and diarrhea that is often bloody. Young children and older adults face the highest risk of hemolytic uremic syndrome, a serious complication that can cause kidney failure. Peeing very little, unusual tiredness, or pale skin after a diarrheal illness need urgent care.
People at higher risk can follow CDC's Listeria prevention advice: avoid deli meats unless heated until steaming hot, choose pasteurized dairy, and skip refrigerated smoked seafood. Washing produce, cooking ground beef thoroughly, and keeping raw meat separate from ready-to-eat foods also lower risk.
Anyone with symptoms should contact a clinician and mention what they ate in recent weeks, since that information helps investigators. Stool or blood tests confirm these infections, and test results feed the national databases that link scattered cases into outbreaks. Antibiotics are used for serious Listeria infections, but they are generally not recommended for E. coli O157:H7 because they may raise the risk of kidney complications.
Unnamed-source outbreaks are common. Some end without a food ever being identified, often because patients cannot remember what they ate weeks earlier or because the product is no longer on shelves. Others lead to recalls after testing finds the outbreak strain in a specific food. Reports of suspected food poisoning can also go to local health departments.
FDA updates its table regularly. MedicalDaily will report when a food source is named or a recall is issued.
Key Questions Answered
What did FDA add to its table? A new Listeria outbreak, reference 1415, with 11 cases and no identified food source.
How much did the E. coli outbreak grow? Outbreak 1421 rose from 25 to 38 cases, and FDA began sample collection.
Is there a product to avoid? Not for these four outbreaks. FDA has not named a food for any of them.
What is traceback? It is the process of tracing a food through the supply chain from consumers back to the farm or manufacturer.
Are the Listeria outbreaks related? FDA has not said they are connected.
Who should be most careful? Pregnant women, newborns, older adults, young children, and people with weakened immune systems.
Published by Medicaldaily.com
