Pertussis (Bordetella pertussis) “Whooping Cough”

2020 Case Definition

CSTE Position Statement Number: 19-ID-08

Clinical Case Definition

In the absence of a more likely diagnosis, a cough illness lasting ≥2 weeks with at least one of the following signs or symptoms:

Paroxysms of coughing, OR
Inspiratory “whoop,” OR
Posttussive vomiting, OR
Apnea (with or without cyanosis)

Laboratory Criteria for Diagnosis

Confirmatory Laboratory Evidence

Isolation of B. pertussis from a clinical specimen
Positive polymerase chain reaction (PCR) for B. pertussis

Epidemiologic linkage

Contact with a laboratory-confirmed case of pertussis.

Case Classification

Probable:

In the absence of a more likely diagnosis, illness meeting the clinical criteria, OR
Illness with cough of any duration, with
- At least one of the following signs or symptoms:
- - Paroxysms of coughing, OR
  - Inspiratory “whoop”, OR
  - Posttussive vomiting, OR
  - Apnea (with or without cyanosis)
- AND
- Contact with a laboratory confirmed case (epidemiologic linkage)

Confirmed:

Acute cough illness of any duration with
- Isolation of B. pertussis from a clinical specimen, OR
- PCR positive for B. pertussis

Classification Table: Criteria for defining a case of Pertussis

Criterion	Confirmed	Probable	Probable
Clinical Evidence
Acute cough illness (any duration)	N		N
Cough ≥ 2 weeks duration		N
Inspiratory whoop		O	O
Paroxysms of coughing		O	O
Post-tussive vomiting		O	O
Apnea (with or without cyanosis		O	O
Absence of a more likely diagnosis		N
Laboratory Evidence
Isolation of B. Pertussis from a clinical specimen	O
Positive PCR for B. Pertussis	O
Epidemiologic Linkage Evidence
Contact with a laboratory-confirmed case (classified as "Confirmed")			N
Criteria to distinguish a new case
N/A
2019 Template

Notes:

N = All “N” criteria in the same column are NECESSARY to classify a case. A number following an “N” indicates that this criterion is only required for a specific disease/condition subtype (see below). If the absence of a criterion (i.e., criterion NOT present) is required for the case to meet the classification criteria, list the absence of criterion as a necessary component.

O = At least one of these “O” (ONE OR MORE) criteria in each category (categories=clinical evidence, laboratory evidence, and epidemiologic evidence) in the same column—in conjunction with all “N” criteria in the same column—is required to classify a case. A number following an “O” indicates that this criterion is only required for a specific disease/condition subtype.

Source: https://cdn.ymaws.com/www.cste.org/resource/resmgr/2019ps/final/19-ID-08_Pertussis_final_7.3.pdf

Date Posted: September 11, 2026