Diphtheria Dr Rob Hicks Diphtheria is a highly contagious bacterial infection that mainly affects the nose and throat.

In this article

What causes it? What are the symptoms?

Who's affected? What's the treatment?

Diphtheria is caused by Corynebacterium diphtheriae. It releases toxins into the blood that can lead to potentially life-threatening complications of the heart, kidneys and central nervous system.

Diphtheria is highly contagious and is easily passed on through sneezing, coughing or even laughing. It can spread by tissues or drinking glasses that have been used by the infected person.

People who have been infected by diphtheria bacteria can infect others for up to four weeks, even if they don't have any symptoms.

Symptoms include a sore throat, fever and swollen lymph glands in the neck. In many cases, a grey membrane grows across the throat making breathing difficult. Cutaneous diphtheria affects the skin, causing sores to develop.

Diphtheria can lead to breathing problems, heart failure, paralysis and sometimes death.

It's more common in children, although it's now rare in developed countries because of vaccination programmes.

Diphtheria requires hospital treatment with an antitoxin to neutralise the diphtheria toxins and antibiotics to kill remaining bacteria.

Patients are isolated and intensive care support may be needed if the heart, kidneys and/or nervous system have been affected. Patients who have recovered are given a full course of diphtheria vaccine.

This article was last medically reviewed by Dr Rob Hicks in January 2008