Listeriosis is a serious infection caused by the germ Listeria monocytogenes. People usually become ill with listeriosis after eating contaminated food. The disease primarily affects pregnant women, newborns, older adults, and people with weakened immune systems. It’s rare for people in other groups to get sick with Listeria infection.
Listeriosis is usually a mild illness for pregnant women, but it causes severe disease in the fetus or newborn baby. Some people with Listeria infections, most commonly adults 65 years and older and people with weakened immune systems, develop severe infections of the bloodstream (causing sepsis) or brain (causing meningitis or encephalitis). Listeria infections can sometimes affect other parts of the body, including bones, joints, and sites in the chest and abdomen.
Symptoms of Listeriosis
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.
Listeriosis is usually diagnosed when a bacterial culture (a type of laboratory test) grows Listeria monocytogenes from a body tissue or fluid, such as blood, spinal fluid, or the placenta.
Listeriosis is treated with antibiotics.
What should I do if I suspect eating contaminated food?
You should seek medical care and tell the doctor about eating possibly contaminated food if you have a fever and other symptoms of possible listeriosis, such as fatigue and muscle aches, within two months after eating possibly contaminated food. This is especially important if you are pregnant, age 65 or older, or have a weakened immune system.
If you ate food possibly contaminated with Listeria and do not feel sick, most experts believe you do not need tests or treatment. Talk with your medical provider if you have questions about what to do after eating possibly contaminated food.
For medical practitioners, read the full PSDS here.
L. Monocytogenes is listed under the HBA Regulations in South Africa.
Source: CDC Canada