Diphtheria (Greek διφθέρα (diphthera) “pair of leather scrolls”) is an upper respiratory tract illness caused by Corynebacterium diphtheriae, a facultative anaerobic, Gram-positive bacterium.[1][2] It is characterized by sore throat, low fever, and an adherent membrane (a pseudomembrane) on the tonsils, pharynx, and/or nasal cavity.[3] A milder form of diphtheria can be restricted to the skin. Less common consequences include myocarditis (about 20% of cases) [4] and peripheral neuropathy (about 10% of cases).[5]