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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)

  • 09-ID-67

Clinical Description

An illness caused by Salmonella enterica serotype Typhi that is often characterized by insidious onset of sustained fever, headache, malaise, anorexia, relative bradycardia, constipation or diarrhea, and nonproductive cough. However, many mild and atypical infections occur. Carriage of serotype Typhi may be prolonged.

Laboratory Criteria For Diagnosis

Isolation of serotype Typhi from blood, stool, or other clinical specimen

Case Classification


A clinically compatible case that is epidemiologically linked to a confirmed case in an outbreak


A clinically compatible case that is laboratory confirmed


Isolation of the organism is required for confirmation. Serologic evidence alone is not sufficient for diagnosis. Asymptomatic carriage should not be reported as typhoid fever. Isolates of Salmonella enterica serotype Typhi are reported to the Enteric Diseases Epidemiology Branch, Division of Foodborne, Waterborne, and Enteric Diseases, National Center for for Emerging and Zoonotic Infectious Diseases, CDC, through the Laboratory-Based Enteric Disease Surveillance (LEDS).   In addition, a National Typhoid and Paratyphoid Fever Surveillance report form should be submitted for all cases (can be found here:

The 1997 case definition appearing on this page was originally published in the 1990 MMWR and re-published in the 2009 CSTE position statement 09-ID-67.1,2 Thus, the 1990, 1997, and 2010 versions of the case definition are identical.


  1. CDC. (1990). Case Definitions for Public Health Surveillance. MMWR, 39(RR-13), 1-43.
  2. CDC. (1997). Case Definitions for Infectious Conditions Under Public Health Surveillance. MMWR, 46(RR-10), 1-55.