and fever. In severe cases, a grey or white patch develops in the throat called a pseudomembrane. This tough, leathery membrane slowly blocks the airway. Starting with a barking cough, similar to that observed in croup, the neck may also swell, in part due to the enlargement of the facial lymph nodes. The pseudomembrane can grow to cover a wide area of the throat, leading to strangulation and death.

Diphtheria can also involve the