Diphtheria is an acute infection of the nose and throat. It is caused by a bacteria (Corynebacterium diphtheria). The bacteria produces a toxin that damages nerves, usually temporarily. Inflammation of the heart muscle can cause permanent damage to the heart and sometimes death. Diphtheria used to occur throughout the world, but especially during the colder months of the year in temperate regions, causing many deaths mainly in children under 10 years old. A vaccine against the effects of diphtheria toxin was developed in 1939, and the disease has been virtually eliminated from Europe and North America where it used to be common.
Diphtheria caused 0.01% of all deaths worldwide in 2002 with an average of 1 death per million people.