ICD-10 Code A37.1 – Whooping cough due to Bordetella parapertussis (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code A37.1 – Whooping cough due to Bordetella parapertussis
What it is
A37.1 identifies pertussis-like illness caused by Bordetella parapertussis. Use it when documentation specifies this organism as the cause of whooping cough.
Clinical signs
Patients commonly have a prolonged paroxysmal cough, possible inspiratory whoop, and posttussive vomiting. Clinical features vary; refer to documentation.
When to use this code
Use A37.1 when the record clearly states whooping cough due to Bordetella parapertussis, or parapertussis infection with pertussis-like symptoms. Code from provider documentation, not from suspicion alone. If the organism is not specified, check documentation.
Do not use for
Do not use this code for pertussis due to Bordetella pertussis, unspecified whooping cough, or a simple cough without confirmed parapertussis. Check documentation.
Coding tip
Confirm the organism name in the final diagnosis, lab report, or assessment before assigning A37.1.