Skip directly to site content Skip directly to search
An official website of the United States government
Here's how you know
Official websites use .gov

A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS

A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

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, primary
  • Syphilis, secondary
  • Syphilis, unknown duration or late
  • Syphilis, Congenital
  • Syphilitic Stillbirth

Clinical Description

A stage of infection caused by T. pallidum in which initial infection has occurred within the previous 12 months, but there are no signs or symptoms of primary or secondary syphilis.

Laboratory Criteria For Diagnosis

Supportive:

  • A current nontreponemal test titer demonstrating fourfold or greater increase from the last nontreponemal test titer, unless there is evidence that this increase was not sustained for >2 weeks.

Subtype(s) Case Definition

Case Classification

Probable

A person with no clinical signs or symptoms of primary or secondary syphilis who has one of the following:

  • No prior history of syphilis, AND a current reactive nontreponemal test (e.g., VDRL, RPR, or equivalent serologic methods), AND a current reactive treponemal test (e.g., TP-PA, EIA, CIA, or equivalent serologic methods), OR
  • A prior history of syphilis and meets the supportive laboratory criteria.

AND evidence of having acquired the infection within the previous 12 months based on one or more of the following criteria:

  • Documented seroconversion or fourfold or greater increase in titer of a nontreponemal test during the previous 12 months, unless there is evidence that this increase was not sustained for >2 weeks
  • Documented seroconversion of a treponemal test during the previous 12 months
  • A history of symptoms consistent with primary or secondary syphilis during the previous 12 months
  • Meets epidemiologic criteria

Epidemiological Criteria:

  • A history of sexual exposure to a partner within the previous 12 months who had primary, secondary, or early non-primary non-secondary syphilis (documented independently as duration <12 months).
  • Only sexual contact (sexual debut) was within the previous 12 months.

Related Case Definition(s)