Diphtheria

Abstract

Diphtheria is a vaccine-preventable infection caused by toxin-producing strains of Corynebacterium diphtheriae. The pathogen’s natural reservoir is the human nasopharynx. Pharyngeal diphtheria is associated with cervical adenopathy, soft tissue swelling of the neck, and the formation of a greyish pseudomembrane on the posterior pharyngeal wall that can become severe enough to impair the patency of the airway. Diphtheria toxin is also associated with cardiac and renal injury. Diphtheria vaccine is derived from diphtheria toxin that has been rendered nontoxigenic while retaining full immunogenicity. The resulting immunogen is referred to as a toxoid. Monovalent diphtheria toxoid vaccine is not available for use. Available diphtheria toxoid vaccines include a variety of combination formulations. Following a full series of vaccine during childhood, booster doses are needed every 10 years to maintain immunity. Vaccination programs are highly effective at preventing disease, but outbreaks continue to occur in areas of the world where vaccination efforts are suboptimal or have been halted because of extreme poverty, civil unrest, or war-like conditions.