Sneezing, coughing, a runny or blocked nose, raised temperature, muscle aches and pains. These are just some of the symptoms of a viral infectious disease all of us have had at least once: the common cold.

However, if we add to this list small greyish-white spots in the mouth, and large blotchy patches all over the body, made up of small red-brown spots, the outcome is a much less common disease, that can even become fatal: rubeola, otherwise known as measles.

Nowadays, thanks to modern technology that allows us to vaccinate against the disease, and improvements in our knowledge of the disease and how to treat it, measles has decreased significantly in the last century. But despite medical advances, outbreaks are still occurring around Britain, and this time, it has especially hit South London.

Public Health England (PHE) has reasoned that this outbreak is linked to “ongoing large outbreaks” in Europe, especially where not everyone has received the MMR vaccine, in places such as Romania (the worst affected country), Italy, Greece and Germany.

The MMR vaccine is a combined vaccination that protects against measles, mumps and rubella. Its full course includes two doses, which are very effective at preventing the contraction of all three highly infectious diseases. The World Health Organisation (WHO) has warned that the sharp rise in measles cases is due to low immunisation coverage, and to reduce the number of cases 95% of the population must be vaccinated, a further 3.4% more than in 2016-17 among young children.

Although measles can still affect adults, children are most susceptible to the virus if they have not been immunised, and can be dramatically affected by it, potentially contracting serious complications such as encephalitis (inflammation of the brain), which can lead to brain damage.

One very famous case of measles encephalitis was that of Roald Dahl's daughter, Olivia, who consequently died of the disease in 1962, as her father explained: “in those days a reliable measles vaccine had not been discovered”. He stated that “it is really almost a crime to allow your child to go unimmunised”.

In the first three months of this year alone, 700 cases have been reported - nearly double the whole of 2017. So, what can be done to try to prevent the outbreak from spreading further? Dr Mary Ramsay, Head of Immunisation at PHE, said: “We want to remind people that measles is not just a disease of young children and we’re seeing many cases in people over 15 years of age. Adults or parents who are unsure if they or their children have been fully vaccinated should check with their GP and make an appointment to receive 2 doses of MMR vaccine.”