Cases of measles across Europe rocketed by 300% last year, as some parents refused to vaccinate their children.

According to new figures from the World Health Organisation (WHO), this led to 20,000 people becoming infected, and 35 deaths.

The viral illness was all but eradicated in Britain before the late 1990s, when the now-discredited Dr Andrew Wakefield wrongly claimed the measles, mumps and rubella jab was linked to autism, the Mirror reports.

In turn, this led to some parents choosing not to vaccinate their children, leaving them at risk of catching it.

Many of these are now young adults or teenagers who, according to the Mirror, are travelling through Europe and going to festivals where there have been outbreaks of measles.

In 2017, there were 282 reported cases of measles in the UK - all caused by people arriving from affected countries - and so far this year there has been 36.

So what is measles, how can you catch it and is it treatable? Here is everything you need to know:

What are the symptoms?

The initial symptoms of measles develop around 10 days after you're infected, according to the NHS.

These are the ones to watch out for:

cold-like symptoms, such as a runny nose, sneezing, and a cough

sore, red eyes that may be sensitive to light

a high temperature (fever), which may reach around 40° C (104° F)

small greyish-white spots on the inside of the cheeks

loss of appetite

tiredness, irritability and a general lack of energy

A few days later, a red-brown blotchy rash will appear. This usually starts on the head or upper neck, before spreading outwards to the rest of the body.

The measles rash appears around two to four days after the initial symptoms and normally fades after about a week.

You'll usually feel most ill on the first or second day after the rash develops.

According to the NHS, the rash:

is slightly itchy for some people

can look similar to other childhood conditions, such as slapped cheek syndrome, roseola or rubella

is unlikely to be caused by measles if the person has been fully vaccinated (had two doses of the MMR vaccine) or had measles before

What is the MMR vaccine?

(Image: David Jones/PA Wire)

The MMR vaccination is a combined treatment which protects against measles, mumps and rubella and is available to all adults and children who have not completed the course.

The full course requires two doses.

Children should be given the MMR vaccine when they are one-years-old. They will have the second injection before starting school, usually at three-years-and-four-months-old.

If you or your child have not been vaccinated it is not too late, and doctors are urging anyone who has never had the jab to get themselves vaccinated.

If you're not sure about your vaccination status, check with your GP.

Is there a treatment for measles?

There is no specific treatment, but the body’s immune system should be able to fight off the illness within a couple of weeks.

However, in severe cases hospital admission may be required.

The NHS recommends paracetamol or ibuprofen to relieve fever, aches and pains.

You should also drink plenty of water to avoid dehydration, and stay off school or work for four days after the rash appears.

How can I prevent it?

The most effective way is the measles, mumps and rubella vaccine.

To prevent a measles outbreak doctors recommend that at least 95% of the population is immunised.

91.9% of UK children were vaccinated against measles between 2015 and 2016, compared to 94.2% the year before.

The World Health Organisation had said people's complacency and fear of vaccines means young children in particular are more susceptible to infection.