Diphtheria is a vaccine-preventable, life-threatening infectious disease which kills up to 1 in 10 of those who get it.
Diphtheria used to be a common childhood illness which killed around 4000 children a year before the introduction of a vaccine. It is hardly seen in countries like the UK any more because of vaccination. However since the start of 2015, two unvaccinated children have died of diphtheria in Europe (one in Spain in 2015 and one in Belgium in 2016).
Symptoms include mild fever, nausea, headache, sore throat and raised heart rate. The bacteria which cause diphtheria very often produce a powerful toxin which kills cells in the mouth, nose and throat. The dead cells quickly build up and form a membrane which can attach to the throat and lead to death by choking. Diphtheria can also affect the heart (causing heart failure and death), and the nerves (causing neurological damage including weakness and numbness of limbs). Even with full medical treatment, it causes death in between 5 and 10 in every 100 cases.
It is usually spread by droplets of moisture containing the bacterium Corynebacterium diphtheriae coughed into the air by someone infected by the disease.
It is not possible to develop natural immunity to diphtheria without getting the disease itself, which involves a 1 in 10 chance of death. The only way to protect your child is vaccination. Babies in the UK are protected by the 5-in-1 vaccine. Follow-up doses are given in the Pre-school Booster and the Teenage Booster vaccines.
Before the vaccine was introduced in 1942, diphtheria killed an average of 4,000 people a year in the UK. The vaccine has been so effective, diphtheria has caused only four deaths in the last twenty years (these people were all unvaccinated).
Around 30% of UK adults between 25 and 29 years old are susceptible to diphtheria, a figure which rises to over 70% for those over 60. (For more information, see this article .)
The disease is still endemic in certain parts of the world, including the former USSR, the Indian subcontinent, South East Asia and South America. People travelling to and emigrating from these parts of the world, together with the lower than ideal vaccination rate in the UK (especially in London), means that the disease has not been totally eradicated from the UK, and therefore those who are not vaccinated are at risk.
The graph below shows that before vaccination was introduced in 1942, there were on average 60,000 cases of diphtheria leading to around 4,000 deaths in the UK each year. Following the introduction of the vaccine, reported cases and deaths dropped dramatically so that it is a matter of isolated cases. In the last two decades, two people have died as a result of infection with C. diphtheriae (one in 1994, one in 2008), and two from respiratory diphtheria caused by C. ulcerans (one in 2000, the other in 2006). All were unvaccinated.
Source: Public Health England