When one hears of people getting sick from contaminated food, they usually think of Salmonella or E. coli, but there is one that is just as common that can be more lethal to certain people.

Have you ever heard of Listeria? It is a bacterium, Listeria monocytogenes that causes an illness known as listeriosis. The bacteria can be found in some raw sprouts, raw milk, soft cheese, smoked seafood, deli meats, cold hotdogs and improperly prepared produce like cantaloupes.

One case reported by the CDC back in 2013 involved contaminated whole cantaloupes. In that outbreak, 147 people in 28 states got sick and 33 died. Most of the deaths occurred in people 65 and older. In another case, 142 people got sick with Listeria from eating a type of soft cheese – queso fresco. In that outbreak, 18 adults and 10 newborns died and it was also linked to 20 miscarriages. A third reported outbreak was linked to pre-cut celery used in chicken salad that was served at hospitals. It sickened 10, with 5 of them dying.

Last week, it was reported that at least 8 people in four states (Michigan, New Jersey, New York and Pennsylvania). All 8 people required hospitalization and one person in Michigan died. This outbreak is said to be linked to sliced deli meat and cheese, but the exact source of the contamination has not been determined as yet.

Listeriosis is particularly dangerous to older people, newborns, people with weakened immune systems and pregnant women. As for pregnant women, the illness may not be that serious for the mom, but can result with a miscarriage, stillbirth or death of the newborn baby.

What makes Listeria so deadly, more so than either Salmonella or E. coli, is that it can cause sepsis (infection in the bloodstream) and it can enter the nervous system causing meningitis and even encephalitis. This is why about 1 out of 5 people who get sick with listeriosis die.

According to the CDC, the symptoms of listeriosis are:

“Listeriosis can cause a variety of symptoms, depending on the person and the part of the body affected. Listeria can cause fever and diarrhea similar to other foodborne germs, but this type of Listeria infection is rarely diagnosed. Symptoms in people with invasive listeriosis, meaning the bacteria has spread beyond the gut, depend on whether the person is pregnant.

• Pregnant women: Pregnant women typically experience only fever and other flu-like symptoms, such as fatigue and muscle aches. However, infections during pregnancy can lead to miscarriage, stillbirth, premature delivery, or life-threatening infection of the newborn.
• People other than pregnant women: Symptoms can include headache, stiff neck, confusion, loss of balance, and convulsions in addition to fever and muscle aches.

People with invasive listeriosis usually report symptoms starting 1 to 4 weeks after eating food contaminated with Listeria; some people have reported symptoms starting as late as 70 days after exposure or as early as the same day of exposure.”

To officially diagnose listeriosis requires growing a culture from a sample of tissue, blood, spinal fluid or other body fluids. Once identified, which takes time, it is treated with antibiotics.

Experts are not suggesting you avoid eating deli meats or cheese, only that you be aware and if believe you may have contracted listeriosis, see your doctor or emergency room as soon as possible.