Corynebacterium diphtheriae Toxoid Antigen (DB10584): A Comprehensive Monograph on its Biochemistry, Clinical Application, and Public Health Significance

Executive Summary & Introduction

Overview of Diphtheria

Diphtheria is an acute, toxin-mediated infectious disease caused by toxigenic strains of the bacterium Corynebacterium diphtheriae.[1] The disease classically manifests in the upper respiratory tract, particularly the nasopharynx, or on the skin.[1] Its hallmark clinical sign is the formation of a dense, gray, adherent pseudomembrane composed of fibrin, bacteria, and inflammatory cells, which covers the pharynx and tonsils.[1] This pseudomembrane can cause severe breathing difficulties and, in advanced cases, lead to airway obstruction and death by suffocation.[4]

The primary virulence factor and the cause of systemic disease is a potent exotoxin secreted by the bacterium.[1] Once absorbed into the circulatory system, the diphtheria toxin is distributed to distant organs, where it can elicit severe and life-threatening complications, including myocarditis (inflammation of the heart muscle) leading to congestive heart failure, and peripheral neuropathy causing paralysis.[1] With a fatality rate of 5-10%, which can be even higher in young children, diphtheria remains a serious global health threat, particularly in regions with inadequate immunization coverage.[7]

The Diphtheria Toxoid: A Cornerstone of Modern Vaccinology