Listeriosis

127 cases in 2024 — near the 5-year baseline of ~285.

What is it?

Listeriosis is caused by Listeria monocytogenes bacteria found in soil, water, and some foods. NYS had 127 cases in 2024. While rare, listeriosis is serious: it causes the greatest number of foodborne illness deaths of any single pathogen in the US. It is particularly dangerous for pregnant people, newborns, elderly adults, and immunocompromised individuals.

How it spreads

Spreads through eating contaminated foods, especially ready-to-eat products such as deli meats, hot dogs eaten without reheating, soft cheeses made from unpasteurized milk, smoked seafood, and refrigerated pâtés. Listeria can grow at refrigerator temperatures, making it unique among foodborne pathogens.

Symptoms

Healthy adults may have mild, flu-like illness. In vulnerable populations: fever, muscle aches, headache, and stiff neck. In pregnancy, listeriosis can cause miscarriage, premature delivery, stillbirth, or serious infection in the newborn, sometimes with few symptoms in the mother.

Who is at risk?

Pregnant people (13 times more likely to get listeriosis than others), adults 65+, immunocompromised individuals, and newborns. The risk during pregnancy is high even with mild maternal illness.

What you can do

Based on NYSDOH annual communicable disease report. Threat level reflects 2024 case counts compared to the 5-year baseline.