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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.

Subtype(s)

  • Syphilis
  • Syphilis, secondary
  • Syphilis, latent
  • Syphilis, early latent
  • Syphilis, late latent
  • Syphilis, latent unknown duration
  • Neurosyphilis
  • Syphilitic stillbirth
  • Syphilis, congenital

Clinical Description

The characteristic lesion of primary syphilis is the chancre, but atypical primary lesions may occur.

Laboratory Criteria For Diagnosis

Demonstration of Treponema pallidum in clinical specimens by darkfield, fluorescent antibody, or equivalent microscopic methods

Subtype(s) Case Definition

Case Classification

Probable

A clinically compatible case with one or more ulcers (chancres) consistent with primary syphilis and a reactive serologic test

Confirmed

A clinically compatible case that is laboratory confirmed

Related Case Definition(s)