The symptoms of a listeria infection, also known as listeriosis, include fever, nausea, diarrhea and muscle aches, explains Mayo Clinic. The infection can spread to the nervous system and cause convulsions, headache, confusion, neck stiffness and loss of coordination.
People who are at risk for listeria include pregnant women and their babies, as well as individuals who have a weak immune system, states Mayo Clinic. Women infected with listeria during pregnancy usually experience mild symptoms. The infection may spread to the baby and cause death before birth, or it can cause a serious infection after the child is born. The symptoms of listeriosis in a newborn include poor feeding habits, irritability, fever and vomiting.
Listeria infections can cause complications that include endocarditis, peritonitis, osteomyelitis, septic arthritis and cholecystitis, according to The Merck Manual Professional Edition. Some patients may develop pleuropneumonia, febrile gastroenteritis, meningitis or cerebritis. Listeriosis is diagnosed with a blood or CSF culture. Serious infections are treated with ampicillin and gentamicin.
Listeriosis is caused by consuming food contaminated with Listeria monocytogenes. On average, approximately 1,600 people are infected with the bacterium every year and 260 of these infections result in death, according to estimates by the Centers for Disease Control and Prevention. Listeria can be found in uncooked meats and vegetables, unpasteurized milk, processed cheese, smoked seafood and processed meat products.