Listeriosis (Listeria monocytogenes)

Clinical Criteria
Any person with at least one of the following five: 

• Fever
• Meningitis, meningoencephalitis, or encephalitis
• Influenza-like symptoms
• Septicaemia
• Localized infections such as arthritis, endocarditis, endophthalmitis, and abscesses

Listeriosis in pregnancy:
Pregnancy-related consequences of Listeria infection defined as:
spontaneous abortion, miscarriage, stillbirth or premature birth during the pregnancy

Listeriosis of newborns defined as one of the following:

• Stillbirth
• Premature birth 

OR

• At least one of the following five in the first month of life (neonatal listeriosis):
  • Meningitis or meningoencephalitis
  • Septicaemia
  • Dyspnoea
  • Granulomatosis infantiseptica
  • Lesions on skin, mucosal membranes or conjunctivae

Laboratory Criteria
At least one of the following two:
Isolation of Listeria monocytogenes or detection of nucleic acid of Listeria monocytogenes from a normally sterile site

In a pregnancy-associated case also:
Isolation of Listeria monocytogenes or detection of nucleic acid from Listeria monocytogenes in a normally non-sterile site (for example, placental tissue, amniotic fluid, meconium, vaginal swab) or from a foetus, stillborn, newborn or the mother

Epidemiological Criteria
At least one of the following four epidemiological links:

• Exposure to a common source
• Human to human transmission (vertical transmission)
• Exposure to contaminated food
• Animal to human transmission

Case Classification
A. Possible case
NA
B. Probable case
Any person meeting the clinical criteria with an epidemiological link
C. Confirmed case
Any person meeting the laboratory criteria for a normal sterile site
OR
In a pregnancy-associated case (mother or newborn in the first month of life) meeting the laboratory criteria, only the mother is to be reported as a case.

Current as of: 22 January 2019

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