Symptoms and Signs of Diphtheria

Medical Author:
Medically Reviewed on 9/12/2022

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 

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.

What is the treatment for diphtheria?

Early diagnosis and treatment result in better outcomes; even with treatment, about 10% of infected patients may die. Two treatments are used together:

  • Antibiotics (for example, penicillin, erythromycin) to kill the bacteria
  • Diphtheria antitoxin to halt bacterial-generated toxin from further damaging tissues

Vaccines are able to prevent most diphtherial infections; there are 4 vaccines (DTaP, Tdap, and Td or Tdap for adults). Your doctor can determine what vaccine, if any, is correct for you.

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Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.