In simple words: This code represents an adverse reaction to a pertussis vaccine, including combinations like DTaP or Tdap, on the initial encounter.

Adverse effect of pertussis vaccine, including combinations with a pertussis component, initial encounter.

Example 1: A 2-month-old infant receives their first DTaP vaccination and develops a fever of 104°F within 48 hours. This is considered an adverse effect and would be coded as T50.A15A., A 12-year-old child receives the Tdap booster shot and experiences significant swelling and redness at the injection site, exceeding the typical mild reaction. This adverse effect is documented and coded with T50.A15A., A pregnant woman receives the Tdap vaccine during her third trimester and develops pain and swelling at the injection site along with a low-grade fever. While not life-threatening, these reactions are documented as an adverse effect using T50.A15A.

Documentation should include the type of pertussis vaccine administered (DTaP, Tdap, or other combination), time of administration, description of the adverse reaction, and onset of the reaction relative to the time of vaccination.Any treatment provided for the adverse reaction should also be documented.

** This code only captures the initial encounter for the adverse effect of the pertussis vaccine. Subsequent encounters for the same adverse reaction would be coded differently. It's important to distinguish between mild, expected reactions and true adverse effects when using this code.