What is diphtheria?

Diphtheria is a serious bacterial infection that affects the mucous membranes of the throat and nose. Although it spreads easily from one person to another, diphtheria can be prevented through the use of vaccines.

Call your doctor right away if you believe you have diphtheria. If it’s left untreated, it can cause severe damage to your kidneys, nervous system, and heart. It’s fatal in about 3 percent of cases, according to the Mayo Clinic.

A type of bacteria called Corynebacterium diphtheriae causes diphtheria. The condition is typically spread through person-to-person contact or through contact with objects that have the bacteria on them, such as a cup or used tissue. You may also get diphtheria if you’re around an infected person when they sneeze, cough, or blow their nose.

Even if an infected person doesn’t show any signs or symptoms of diphtheria, they’re still able to transmit the bacterial infection for up to six weeks after the initial infection.

The bacteria most commonly infect your nose and throat. Once you’re infected, the bacteria release dangerous substances called toxins. The toxins spread through your bloodstream and often cause a thick, gray coating to form in these areas of the body:

  • nose
  • throat
  • tongue
  • airway

In some cases, these toxins can also damage other organs, including the heart, brain, and kidneys. This can lead to potentially life-threatening complications, such as:

Children in the United States and Europe are routinely vaccinated against diphtheria, so the condition is rare in these places. However, diphtheria is still fairly common in developing countries where immunization rates are low. In these countries, children under age 5 and people over age 60 are particularly at risk of getting diphtheria.

People are also at an increased risk of contracting diphtheria if they:

  • aren’t up to date on their vaccinations
  • visit a country that doesn’t provide immunizations
  • have an immune system disorder, such as AIDS
  • live in unsanitary or crowded conditions

Signs of diphtheria often appear within two to five days of the infection occurring. Some people don’t experience any symptoms, while others have mild symptoms that are similar to those of the common cold.

The most visible and common symptom of diphtheria is a thick, gray coating on the throat and tonsils. Other common symptoms include:

Additional symptoms may occur as the infection progresses, including:

If you have poor hygiene or live in a tropical area, you may also develop cutaneous diphtheria, or diphtheria of the skin. Diphtheria of the skin usually causes ulcers and redness in the affected area.

Your doctor will likely perform a physical exam to check for swollen lymph nodes. They’ll also ask you about your medical history and the symptoms you’ve been having.

Your doctor may believe that you have diphtheria if they see a gray coating on your throat or tonsils. If your doctor needs to confirm the diagnosis, they’ll take a sample of the affected tissue and send it to a laboratory for testing. A throat culture may also be taken if your doctor suspects diphtheria of the skin.

Diphtheria is a serious condition, so your doctor will want to treat you quickly and aggressively.

The first step of treatment is an antitoxin injection. This is used to counteract the toxin produced by the bacteria. Make sure to tell your doctor if you suspect you might be allergic to the antitoxin. They may be able to give you small doses of the antitoxin and gradually build up to higher amounts. Your doctor will also prescribe antibiotics, such as erythromycin or penicillin, to help clear up the infection.

During treatment, your doctor may have you stay in the hospital so you can avoid passing your infection on to others. They may also prescribe antibiotics for those close to you.

Diphtheria is preventable with the use of antibiotics and vaccines.

The vaccine for diphtheria is called DTaP. It’s usually given in a single shot along with vaccines for pertussis and tetanus. The DTaP vaccine is administered in a series of five shots. It’s given to children at the following ages:

  • 2 months
  • 4 months
  • 6 months
  • 15 to 18 months
  • 4 to 6 years

In rare cases, a child might have an allergic reaction to the vaccine. This can result in seizures or hives, which will later go away.

Vaccines only last for 10 years, so your child will need to be vaccinated again around age 12. For adults, it’s recommended that you get a combined diphtheria-tetanus-pertussis booster shot once. Every 10 years afterward, you’ll receive the tetanus-diphtheria (Td) vaccine. Taking these steps can help prevent you or your child from getting diphtheria in the future.