A 2-month-old infant presents with fever and seizures 24 hours after receiving DTP-IPV-Hib pentavalent vaccine. Neurology evaluates the child and finds the febrile seizure to be simple. This event is classified under AEFI monitoring. Which of the following is the CORRECT classification of this event under WHO AEFI causality criteria?

• A Coincidental — febrile illness of another cause, with vaccine temporally coincident
• B Vaccine reaction — febrile seizure is a known expected adverse event of pertussis component; causal link established ✓
• C Immunization error — incorrect vaccine preparation
• D Unknown — febrile seizure cannot be classified under any AEFI category

Explanation

Under WHO 2013 AEFI causality assessment criteria, febrile seizure post-DTP is classified as a 'vaccine product-related reaction' (vaccine reaction) — febrile seizures occurring within 48 hours of whole-cell pertussis DTP are a known, expected adverse reaction related to the pyrogenic properties of the pertussis component, with a well-established causal association. This does NOT mean the vaccine caused epilepsy — simple febrile seizures after DTP have no long-term neurological consequences. Coincidental would apply if there is evidence of another independent cause. Immunization errors involve cold chain failures or improper reconstitution.

Reference: Ghai Essential Pediatrics, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.