• Thu. Jun 30th, 2022

Diphtheria is a serious bacterial infection that usually affects the mucous membranes of the throat and nose. Widespread vaccination against diphtheria is very rare in the United States and other developed countries. However, diphtheria is still prevalent in many countries with limited health care or vaccination options.

Diphtheria can be treated with medication. But in advanced stages, diphtheria can damage the kidneys, heart, and nervous system. Even with treatment, diphtheria can be dangerous, especially in children.


Diphtheria symptoms usually begin 2 to 5 days after a person becomes infected. Signs may include:

  • Fever and chills
  • The dense, gray membrane covering the throat and tonsils
  • A sore throat and hoarseness
  • Swollen glands (enlarged lymph nodes) in the neck
  • Difficulty breathing or rapid breathing
  • Nasal discharge
  • Tiredness

In some people, infection with diphtheria-causing bacteria causes only a mild illness or no obvious symptoms at all. Infected people who stay unaware of their sickness are known as carriers of diphtheria. Because they can spread the infection without getting sick

Skin (cutaneous) diphtheria

The second type of diphtheria affects the skin, causing pain, redness, and swelling just like any other bacterial skin infection. Ulcers covered by a gray membrane may also be a sign of skin diphtheria. 

Although it is most common in tropical climates, skin diphtheria occurs in the United States. This can happen especially among those with poor hygiene living in a crowded environment.


Diphtheria is caused by the bacterium Corynebacterium diphtheriae. The bacterium usually grows on or near the surface of the throat or skin. C. Diphtheria is spread by:

  • Airborne droplets. When the infected person sneezes or coughs and releases a fog of contaminated water droplets, nearby people may inhale C.diphtheria. Diphtheria is easily spread this way, especially in crowded situations.
  • The contaminated personal or household items. People sometimes get diphtheria by handling an infected person’s items such as used tissues or hand towels that can be contaminated with bacteria.
  • Touching an infected wound can also replace the bacteria that cause diphtheria.

People infected with the diphtheria bacterium and those who are not treated can be infected even if they do not show any symptoms.

Risk factors

People at high risk for catching diphtheria include:

  • Children and adults without renewed vaccines
  • People living in crowded or unsanitary conditions
  • Anyone traveling to an area with a high incidence of diphtheria infections

When to see a doctor

Call your family doctor instantly if you or your child has diphtheria. Schedule an appointment if you do not know if your child has been vaccinated against diphtheria. Make sure your vaccines are current.