A new Listeria monocytogenes outbreak from an unknown source has been detected by the Food and Drug Administration.

At least 34 patients are confirmed in the outbreak, which was first posted by the FDA on Jan. 15. The agency has begun traceback but has not reported what foods are being traced. The FDA has not reported where the patients live.

About Listeria infections
Food contaminated with Listeria monocytogenes may not look or smell spoiled but can still cause serious and sometimes life-threatening infections. Anyone who has developed symptoms of Listeria infection should seek medical treatment and tell their doctors about possible Listeria exposure.

It can take up to 70 days after exposure to Listeria for symptoms of listeriosis to develop. 

Symptoms of Listeria infection can include vomiting, nausea, persistent fever, muscle aches, severe headache, and neck stiffness. Specific laboratory tests are required to diagnose Listeria infections, which can mimic other illnesses. 

Pregnant women, the elderly, young children, and people such as cancer patients who have weakened immune systems are particularly at risk of serious illnesses, life-threatening infections, other complications and death. Although infected pregnant women may experience only mild, flu-like symptoms, their infections can lead to premature delivery, infection of the newborn, or even stillbirth.

In other outbreak news, the patient count for another Listeria monocytogenes outbreak has increased to 32, up one since this past week. The outbreak was first reported by the FDA on Dec. 26, 2024. 

The agency has begun traceback but has not reported what food is being traced. The agency has also begun an on-site inspection and is conducting sample testing but has not reported what location is being inspected or what kind of samples are being tested.

In an E. coli O145:H28 outbreak, the patient count is holding steady at eight. The FDA is not reporting where the patients live. The FDA first reported the outbreak on Dec. 11. The agency has begun traceback efforts but is not yet reporting what food is being traced.

For an E. Coli O157:H7 infections, the FDA has concluded its investigation without identifying a source of the pathogen. The agency did initiate a traceback investigation, but did not report food it was tracing. A total of 26 people were sickened in the outbreak. The FDA did not report where the patients lived.

(To sign up for a free subscription to Food Safety News,click here)