Mumps – a contagious viral infection that causes swelling of the glands – has been in the news this week after the confirmation of the outbreak at two universities.
A total of 223 suspected cases were reported, with 40 confirmed by Nottingham Trent University and University of Nottingham.
This has now risen to 241 suspected cases, 51 confirmed by Public Health England (PHE).
BBC News took a look at why this is and a & # 39 is university students are still in danger.
Where else is this happening?
The figures seem to be particularly high in Nottingham.
PHE said the latest data showed cases of mumps in the UK declined in 2018, with 1,024 confirmed cases compared with 1796 in 2017.
There also have been several reported cases in the universities of Bath, Hull and Liverpool, and in the US – in particular Temple University in Philadelphia, who has recorded about 100 people with signs of infection.
There does not appear any reason why the number of Nottingham is much higher, although experts say it may be that there are in the city that are not protected.
Professor Jonathan Ball of Nottingham University – an expert in the field of viruses and viral vaccines and treatments, – he said influenced the student because they are gathered in "close proximity to a fairly long period of time."
This will include dormitories, lecture halls or nightclubs that keep certain nights aimed at students.
"virus [could] spread quite easily, especially if there is a relatively large number of people who have not been vaccinated, "he said.
Marine biology student at the University of Hull, who did not want to give his name, said that he began to feel ill while on a trip to the island of Cumbrae in Scotland.
He said that the local physician diagnosed mumps, but also sent a tampon in order to confirm that the pig with & # 39 is a disease in England and Wales.
19-year-old man, who said he knew of at least two others who had symptoms were to be isolated and well-fitting, avoiding public transport because of the risk of infecting others.
You can catch it if you have been vaccinated?
Yes. Dr. Vanessa McGregor, of the RNU, said he had seen growth in numbers in recent years, with teenagers and young adults who have not had two doses of MMR vaccine, "particularly vulnerable".
NHS says that the vaccine & # 39 is part of the regular childhood immunization schedule, in which the child gets one dose when they are 12 to 13 months and the second for three years and four months.
Dr. McGregor urged those who have not had MMR vaccine – or had received only one dose – to ensure that they have picked up an offer MMR (measles, mumps and rubella) vaccine.
Hull University student also said that it was "strange" he had contracted, because he was both a dose and it was confirmed by his father.
According to Professor Ball, mumps part of the vaccine with the & # 39 is "less effective."
He said: "For the mumps vaccine, we expect that about 88% of people vaccinated to be protected, while for measles vaccine, it reaches 98%.
"If you add an unvaccinated people in the mix, it is easy to see how a relatively contagious virus as mumps can spread so easily."
He said it was even more complicated, because some people who are infected show little or no symptoms at all.
However, if the majority were vaccinated prone to infection benefit from the "herd immunity" level according to experts, to protect people from diseases.
But, as Professor Ball says. "If you start to reduce the number of people vaccinated, that the protection of the herd does not exist"
Why is the MMR vaccine uptake is reduced?
According to BBC Health Editor X & # 39; nd Pim, cause absorption which reduces it was not clear in many countries.
"Skoda" work discredited scientist and struck-off medic Andrew Wakefield in the 1990s "helped fuel the fire of anti-vaccine movement," according to Prof Ball.
In 1998, the doctor led the research associated with the MMR vaccine with autism that affect the coverage of the vaccine, with the frequency decreasing to 80% at the end of 1990 and a low of 79% in 2003.
Prices partially recovered after the study has been refuted, but on the & # 39; the amount of the anti-vaccine sentiment in social networks has increased in recent years.
This has resulted in health and social welfare secretary Matt Hancock to call new laws to force companies to social media to remove content that is contributed to misinformation about vaccines.
Professor Ball said that there have been rare "side effects" of vaccines, and even if there is, the benefits outweigh them.
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"Because we have lived through the golden age of vaccination, we have forgotten how bad, and sometimes even fatal, these viral infections may be," he said.
Or & # 39 are students and others are still in danger?
Dr. Natalie Riddell, a teacher in the field of immunology and aging at the University of Surrey, said reduced number of people vaccinated against any infectious disease was dangerous.
"Children and the immuno-compromised people [such as the elderly or those receiving chemotherapy] hope for the rest of us to be vaccinated to prevent the spread of disease, "she said.
"It is absolutely not necessary for people to risk their friends and family & # 39; and ill or even die from measles or mumps, as there is a safe and effective vaccine to protect against both."
Professor Ball said poor vaccine uptake across the world has led to an increase in outbreaks of mumps and measles, and we must "wait things worse" before they get better.
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