Symptoms and Signs of Diphtheria

Medical Author: John P. Cunha, DO, FACOEP
Medically Reviewed on 3/11/2019

Doctor's Notes on Diphtheria

Diphtheria is a contagious infectious disease that primarily affects the upper respiratory tract (respiratory diphtheria). Vaccination programs have significantly decreased the incidence of diphtheria but serious outbreaks may occur when vaccination rates decline. Respiratory diphtheria in U.S. is currently a rare disease that has largely been eliminated through effective vaccination programs.

Early symptoms of respiratory diphtheria may be similar to a viral upper respiratory infection, but symptoms of diphtheria become more severe with the progression of the disease. Symptoms of respiratory diphtheria may include sore throat, fever, hoarseness, difficulty swallowing, feeling unwell (malaise), weakness, headache, cough, nasal discharge (that may contain pus or blood-tinged fluid), enlarged lymph nodes in the neck and neck swelling (producing a "bull neck" appearance), and difficulty breathing. Later symptoms respiratory diphtheria may include an adherent thick, gray membrane (pseudomembrane) forming over the lining tissue of the tonsils, pharynx, and/or nasal cavity. If this pseudomembrane extends into the larynx and trachea it can obstruct the airway and result in suffocation and death.

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