Under a magnification of 1125X, this Giemsa-stained photomicrograph revealed the presence of Gram-positive Corynebacterium sp. bacteria. Some species of the genus Corynebacterium, are actually a part of the normal population of human skin flora, however, one specie, Corynebacterium diphtheriae, causes an upper respiratory tract illness known as diphtheria.
Respiratory diphtheria presents as a sore throat with low-grade fever and an adherent membrane of the tonsils, pharynx, or nose. Neck swelling is usually present in severe disease. Cutaneous diphtheria presents as infected skin lesions which lack a characteristic appearance.
Toxin-producing strains of Corynebacterium diphtheriae.
Direct person- to-person transmission by intimate respiratory and physical contact. Cutaneous lesions are important in transmission.