The World Health Organisation has confirmed that the UK has lost it's 'measles free' status.

Measles is a highly infectious disease that can only be controlled with a vaccination.

In 2017 the World Health Organization declared that the UK had eliminated measles, however, that elimination status has not been maintained.

Here is why the UK has lost this status and what is being done to stop it spreading.

Why have we lost elimination status?

World Health Organisation (WHO) defines measles elimination as the absence of circulating measles, in the presence of high vaccine coverage, along with good systems to identify cases of the disease.

In countries that have eliminated measles, measles can still occur, but these will be isolated cases that only have limited spread within the community.

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The UK initially achieved WHO measles elimination status in 2017, based on data from 2014-2016.

However, in 2018, there was a marked increase in the number of confirmed measles cases, with 991 confirmed cases in England and Wales, compared with 284 cases in 2017.

Based on this, WHO determined that the UK could no longer be consider as ‘eliminated’ and that transmission of measles had been re-established.

Why have we seen an increase in measles cases?

Measles remains endemic in many countries around the world and there are currently several large outbreaks in countries across Europe where MMR vaccine uptake has been low.

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Public Health England says: "Until measles elimination is achieved globally we will continue to see importations of the measles virus to the UK and in order to limit spread within the UK, it is important to maintain high coverage of two doses of the MMR vaccine in the population."

As measles is highly infectious, even small declines in uptake can have an impact, and anyone who has not received 2 doses of MMR vaccine is at risk, particularly those travelling to countries affected by the ongoing, large outbreaks.

What is being done to combat outbreaks of measles?

While there has been an increase in measles over the past three years, it’s important to remember that measles remains uncommon in the UK because of the effective MMR vaccination programme.

Before the measles vaccine was introduced in 1968, hundreds of thousands of cases occurred each year.

PHE continues to call for those who missed out on their vaccine at the scheduled time to make an appointment now and we are running a public-facing campaign called Value of Vaccines to help share messages and information on vaccination, including MMR.

Elimination can only be sustained by maintaining and improving coverage of the MMR vaccine.