A septicaemic illness usually due to Haemophilus influenzae which includes an acute inflammatory OEDEMA of the EPIGLOTTIS. It progresses very rapidly and a child can be dangerously ill – or even die – within hours of onset. Once recognised, however, it is easily and successfully treated by immediate transfer to hospital for emergency intubation and ventilation and use of antibiotics and steroids. Fortunately it is now very rare as a result of the introduction of haemophilus vaccine into the primary vaccination course of infants. (See LARYNGO-TRACHEO-BRONCHITIS.)