رضيع عمره ٤ أشهر غير مطعّم لأن أهله أجّلوا التطعيمات، كان عنده زكام أسبوعاً، والآن عنده نوبات سعال متتالية شديدة تنتهي بشهقة عالية وقيء، وأحياناً يزرق أثناء النوبة. بين النوبات يبدو بخير، والحرارة طبيعية. ما التشخيص الأرجح؟

A 4-month-old whose parents delayed vaccinations had a cold for a week and now has bouts of severe repeated coughing ending in a loud whoop and vomiting, sometimes turning blue. Between bouts he looks well and is afebrile. What is the most likely diagnosis?

1. Pertussis (whooping cough)
2. Reflux with aspiration of milk
3. Viral croup in a young infant
4. RSV bronchiolitis

Answer: A) Pertussis (whooping cough). Paroxysmal coughing with a whoop, post-tussive vomiting and cyanosis in an unvaccinated infant is classic pertussis; infants may have apnoea. Azithromycin, droplet precautions, contact prophylaxis and maternal vaccination in pregnancy are key.