National case definition: Pertussis

Date of last revision/review: May 2008

National notification

Only confirmed cases of disease should be notified.

Type of surveillance

Routine case-by-case notification to the federal level

Enhanced, active case-by-case notification by paediatric tertiary care hospitals involved in the Immunization Monitoring Program, Active (IMPACT)

Case classification

Confirmed case

Laboratory confirmation of infection:

• isolation of Bordetella pertussis from an appropriate clinical specimen

  or

• detection of B. pertussis DNA from an appropriate clinical specimen and one or more of the following:
  • cough lasting 2 weeks or longer
  • paroxysmal cough of any duration
  • cough with inspiratory “whoop”
  • cough ending in vomiting or gagging, or associated with apnea

  or

• Epidemiologic link to a laboratory-confirmed case and one or more of the following for which there is no other known cause:
  • paroxysmal cough of any duration
  • cough with inspiratory "whoop"
  • cough ending in vomiting or gagging, or associated with apnea

Probable case

Cough lasting 2 weeks or longer in the absence of appropriate laboratory tests and not epidemiologically linked to a laboratory-confirmed case and one or more of the following, with no other known cause:

• paroxysmal cough of any duration
• cough with inspiratory “whoop”
• cough ending in vomiting or gagging, or associated with apnea

Suspect case

One or more of the following, with no other known cause:

• paroxysmal cough of any duration
• cough with inspiratory “whoop”
• cough ending in vomiting or gagging, or associated with apnea

ICD code(s)

ICD-10 code(s)

A37 Whooping cough (pertussis)

ICD-9/ICD-9CM code(s)

033 Whooping cough (pertussis)

Comments

Probable and suspect case definitions are provided as guidelines to assist with case finding and public health management, and are not for national notification purposes.

Laboratory test results should be interpreted in the context of the clinical presentation of the patient.

Detection of B. pertussis by culture has a limited/low sensitivity and high specificity. This may result in under-reporting of cases.

References

Health Canada. National Consensus Conference on Pertussis. CCDR 2003;29(S3):1-39.

Public Health Agency of Canada. Proceedings of the National Microbiology Laboratory Pertussis Workshop. CCDR 2006;32(S4):1-22.

Previous case definitions

Canadian Communicable Disease Surveillance System: disease-specific case definitions and surveillance methods. Can Dis Wkly Rep 1991;17(S3).

Case definitions for diseases under national surveillance. CCDR 2000;26(S3).