Commonly, symptoms of late-onset listeriosis appear about two weeks after birth.

Listeriosis may cause flu-like symptoms and the infection can be transmitted prenatally even if the mother has no symptoms.

Persons with listeriosis may develop flu-like symptoms such as fever, headache, nausea and vomiting, tiredness, and diarrhea.

During pregnancy, listeriosis often causes miscarriage or stillbirth.

Listeriosis is food poisoning caused by eating foods contaminated with the Listeria. The symptoms of listeriosis include headache, stiff neck, confusion, loss of balance, high fevers, convulsions, and fatigue.