An illness that results from INFECTION with the bacterium Corynebacterium diphtheriae. Routine childhood IMMUNIZATION has made diphtheria rare in the United States, though the infection can occur in people who do not receive a booster VACCINE every 10 years and is common in other parts of the world.
Infection may involve the NOSE and THROAT (respiratory diphtheria) or the SKIN (cutaneous diphtheria). C. diphtheriae BACTERIA that infect the throat produce a toxin that causes a thick layer of cells and mucus to accumulate in the throat, forming a membrane that impairs BREATHING. Respiratory diphtheria is life threatening and requires urgent administration of diphtheria ANTITOXIN, which counters the toxin the C. diphtheriae bacteria produce, in combination with ANTIBIOTIC MEDICATIONS to kill the C. diphtheriae bacteria (typically erythromycin or penicillin G). Diphtheria that occurs in the United States is most often cutaneous. Cutaneous diphtheria causes painful, red sores on the skin. Antibiotic therapy is often adequate to treat the infection, though sometimes doctors also administer diphtheria antitoxin.
The INCUBATION PERIOD for either type of diphtheria is two to five days after exposure. The infection is contagious for up to two weeks after symptoms emerge. The course of uncomplicated illness is four to six weeks. Respiratory diphtheria (especially when untreated) may result in complications that include MYOCARDITIS (INFLAMMATION and infection of the HEART MUSCLE), NEURITIS, RESPIRATORY FAILURE, and death. Childhood immunization with booster vaccines every 10 years is the most effective means of prevention. Some people are carriers of C. diphtheriae bacteria, which requires human hosts for survival. Carriers have the infection present in their bodies but do not become ill, though they can pass the infection to others. ANTIBIOTIC PROPHYLAXIS prevents infection in people who are exposed to C. diphtheriae.
See also CHILDHOOD DISEASES; PREVENTIVE HEALTH CARE AND IMMUNIZATION.