Diphtheria is caused by a bacterial infection usually starting a few days after being infected.
It is spread through the air after affected people cough and sneeze.
Whilst symptoms can be mild, they can develop rapidly and the condition can become fatal.
Symptoms usually start with a fever and sore throat and then develop showing whitish patches in the throat, breathing problems, barking cough, swollen necks ( due to enlarged lymph nodes) and closing the airways.
It can also affect the skin and usually needs intravenous antibiotics in hospital when serious.
The risks for travellers
Diphtheria is rare in the UK as Diphtheria vaccination is part of the childhood immunisation programme. However occasionally people have missed vaccination so its important to check all childhood vaccinations have been received.
Travelling adults should receive boosters every 10 years.
In the UK the vaccination is combined with Tetanus and Polio vaccination and is known as DTP.