In infants, symptoms of listeriosis may be seen in the first few days of life and may include:
Late-appearing infection in the infant (symptoms appear age 5 days or older) and infection in children is often seen as meningitis.
In adults, the disease may take many forms depending on what organ or organ systems are infected. It may occur as meningitis, pneumonia, septicemia, and endocarditis, or in milder form as abscesses, skin lesion, and conjunctivitis.
If a pregnant woman becomes infected, it can lead to:
Laboratory tests may be done to detect the bacteria in amniotic fluid, blood, and urine. A CSF culture may be performed.
Note: There are no special clinical signs to tell the difference between menigitis caused by listeria from other types of meningitis.
Mead P, Slutsker L, Dietz V, et al. Food-Related Illness and Death in the United States. Emerg Infect Dis. 1998; 5(5):607-625.
Tappero J, Schuchat A, Deaver K, Mascola L, Wenger J, for the Listeriosis Study Group. Reduction in the incidence of human listeriosis in the United States: Effectiveness of prevention efforts? JAMA. 1995; 273(14):1118-1122.