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NOTE: A surveillance case definition is a set of uniform criteria used to define a disease for public health surveillance. Surveillance case definitions enable public health officials to classify and count cases consistently across reporting jurisdictions. Surveillance case definitions are not intended to be used by healthcare providers for making a clinical diagnosis or determining how to meet an individual patient’s health needs.

CSTE Position Statement(s)

  • 99-ID-03

Clinical Description

In adults, invasive disease caused by Listeria monocytogenes manifests most commonly as meningitis or bacteremia; infection during pregnancy may result in fetal loss through miscarriage or stillbirth, or neonatal meningitis or bacteremia. Other manifestations can also be observed.

Laboratory Criteria For Diagnosis

  • Isolation of L. monocytogenes from a normally sterile site (e.g., blood or cerebrospinal fluid [CSF] or, less commonly, joint, pleural, or pericardial fluid)
  • In the setting of miscarriage or stillbirth, isolation of L. monocytogenes from placental or fetal tissue

Case Classification


A clinically compatible case that is laboratory-confirmed


The usefulness of other laboratory methods such as fluorescent antibody testing or polymerase chain reaction to diagnose invasive listeriosis has not been established.

The 2000 case definition appearing on this page was re-published in the 2003 CSTE position statement 03-ID-01 and in the 2009 CSTE position statement 09-ID-46. Thus, the case definitions in CSTE position statements 99-ID-03, 03-ID-01, and 09-ID-46 are identical.

Related Case Definition(s)