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.

Clinical Description

Meningococcal disease manifests most commonly as meningitis and/or meningococcemia that may progress rapidly to purpura fulminans, shock, and death. However, other manifestations might be observed.

Laboratory Criteria For Diagnosis

Isolation of Neisseria meningitidis from a normally sterile site (e.g., blood or cerebrospinal fluid [CSF] or, less commonly, joint, pleural, or pericardial fluid)

Case Classification

Probable

A case with a positive antigen test in CSF or clinical purpura fulminans in the absence of a positive blood culture

Confirmed

A clinically compatible case that is laboratory confirmed

Comments

Positive antigen test results from urine or serum samples are unreliable for diagnosing meningococcal disease.

Related Case Definition(s)