National Infant Immunization Week is April 23-30 this year. This week, the History of Vaccines blog will feature posts about several diseases that can be prevented by vaccination of infants.
Diphtheria, now nearly unknown in the United States, was once a common childhood affliction. In 1921 the country recorded more than 200,000 cases and more than 15,000 deaths, with the highest percentage of fatal cases among children younger than five. Although the last recorded case in the United States was in 2003, diphtheria remains endemic in many countries.
The disease is caused by a bacterium, Corynebacterium diphtheria, although the actual damage is not done by the bacterium itself. Instead, it secretes a toxin that damages the body's tissues. The most unique symptom of diphtheria is a thick gray substance that can spread over the nasal tissues, tonsils, larynx, and/or pharynx. This substance, called a pseudomembrane, can block the airways; in fact, diphtheria was known in Spain as "el garatillo" -- "the strangler." The toxin produced by the bacterium can also travel through the bloodsteam and damage other organs. More