Most adult infections appear to be subclinical, but clinical infections ranging from mild to severe have been reported. Most symptomatic adult infections occur in immunocompromised patients and in those at the extremes of age, but adult infections in farmers and veterinarians do occur. Listeriosis is associated with increased susceptibility among pregnant individuals, who account for 1 in 4 reported cases in the United States. Infections during pregnancy can lead to stillbirth.
Severe infection can be manifested with meningitis, gastrointestinal symptoms and signs, or a glandular fever-like illness. Hematogenous spread and widespread dissemination is rare.
Cutaneous involvement outside of the neonatal period is rare and usually occurs from direct inoculation of the skin in farmers or veterinarians who are exposed to animal products of conception.
Pediatric patient considerations: As with adults, in children, infection and illness are more likely in the immunocompromised. Infection can occur by ingestion of contaminated or unpasteurized milk or ingestion of cheeses from unpasteurized milk.
The highest incidence of disease is in the neonatal period. See neonatal listeriosis for more information.
A32.9 – Listeriosis, unspecified
4241002 – Listeriosis
- Other bacterial meningitis
- Fungal meningitis
- Mycobacterial meningitis (see atypical mycobacterial infection)
- Sepsis from other types of bacteremia