Key facts Diphtheria is a highly contagious infection that primarily affects the mouth, nose and throat, and sometimes the skin It is caused by a bacteria that produces a toxin which can damage the heart and nerves Diphtheria is a vaccine-preventable disease, but multiple doses are needed to maintain immunity Without proper treatment, diphtheria can be fatal in around 30 per cent of cases, with young children at higher risk Diphtheria has been rare in the UK since routine vaccinations were introduced in 1942 – although there is a small risk of catching it while travelling Overview Diphtheria is a contagious disease caused by the bacterium Corynebacterium diphtheriae . It spreads through coughs and sneezes, or by close contact with an infected individual. Some infected people may not show symptoms but can still spread the bacteria, while others may only experience mild illness.…