Diphtheria is a childhood respiratory infection that is now rare in developed countries.
It is caused by infection of the throat and trachea (the tube leading to the lungs) by the bacterium Corynebacterium diphtheriae that releases a toxin that is responsible for most of the symptoms and complications. It spreads from one person to another in the breath, and the incubation period is two to seven days.
Symptoms include a sore swollen throat, fever, nasal discharge, hoarse voice, overwhelming tiredness, weakness and muscle aches. A thick, grey, sticky discharge forms a membrane across the throat that the patient constantly fights to clear. The diagnosis is confirmed by throat swabs, and heart involvement by an electrocardiograph (ECG).
Rapid, early treatment is critical and involves diphtheria antitoxin injection, antibiotics (kill the bacteria but do not remove the toxin), and medications to control or prevent complications. In severe cases a tracheotomy (cut into the front of the throat) is performed to allow air into the lungs.
Diphtheria can be totally prevented by vaccination. These vaccinations were first introduced in the 1930s. It is normally given in combination with the tetanus vaccine (and sometimes other vaccines) at two, four, six and eighteen months of age, then at four years and every ten years through life.
Severe cases may affect the heart, nose, skin and nerves. Survivors may be affected for life by damage to the heart or lungs.
The death rate varies from 10% to 30% and most deaths occur within the first day or two. Survivors improve in a few days but must be kept at rest for at least three weeks to prevent complications, as it will take this time to for all the toxin to be removed from the body.