Mumps - a contagious viral infection that causes swelling of the glands - has been in the news this week following a confirmed outbreak at two universities.
A total of 223 suspected cases were reported, with 40 confirmed, across Nottingham Trent University and the University of Nottingham.
That has now risen to 241 suspected cases with 51 confirmed by Public Health England (PHE).
BBC News has taken a look at why this is and whether university students are still at risk.
Where else is this happening?
The numbers seem particularly high in Nottingham.
PHE said latest figures showed cases of mumps in England had decreased in 2018, with 1,024 confirmed cases compared with 1,796 in 2017.
There have also been a handful of reported cases at the universities of Bath, Hull and Liverpool and in the US - specifically Temple University, in Philadelphia, which has recorded about 100 people with signs of the infection.
There does not appear to be any reason as to why the Nottingham numbers are much higher, though experts have said it could be that there are more in the city who are not immune.
Professor Jonathan Ball, from the University of Nottingham - an expert in viruses and viral vaccines and treatments - said it was affecting students because they gathered in "close proximity for fairly large periods of time".
This would include in halls of residence, lecture theatres or even at nightclubs, which hold specific nights aimed at students.
"The virus [could] spread fairly easy, especially if there are relatively large numbers of people who have not been vaccinated," he said.
A marine biology student at the University of Hull, who did not want to give his name, said he started feeling ill while on a field trip to the Isle of Cumbrae in Scotland.
The 19-year-old, who said he knew at least two others who had the symptoms, had to be isolated and driven home, avoiding public transport because of the risk of others being infected.
Can you catch it if you have been vaccinated?
Yes. Dr Vanessa MacGregor, from PHE, said it had seen a rise in figures recently, with teenagers and young adults who have not had two doses of the MMR vaccine "particularly vulnerable".
The NHS says the vaccine is part of the routine childhood immunisation schedule, in which a child is given one dose when they are 12 to 13 months old, and a second at three years and four months.
Dr MacGregor urged those who have not had the MMR vaccine - or only received one dose - to ensure they took up the offer of MMR (measles, mumps and rubella) vaccination.
The University of Hull student also said it was "strange" he had contracted the infection because he had received both doses and this had been confirmed by his father.
According to Prof Ball, the mumps part of the vaccine is the "least effective".
He said: "For the mumps vaccine, we expect about 88% of people vaccinated to be protected, whereas for the measles vaccine this is as high as 98%.
"If you then add unvaccinated people into the mix, it is easy to see how a relatively contagious virus as mumps can spread so easily."
He said this was further complicated, because some people who are infected show little or no symptoms at all.
However, if the majority were vaccinated, those susceptible to the infection would benefit from "herd immunity", the level considered by experts to protect a population from a disease.
But, as Prof Ball states: "If you start to reduce the numbers of people being vaccinated, then that herd protection just isn't there."
Why is uptake of the MMR vaccine declining?
According to BBC Health Editor Hugh Pym, the reason for uptake declining in many countries was not clear.
The "damaging" work of discredited scientist and struck-off medic Andrew Wakefield in the 1990s "helped fuel the fire of the anti-vaccine movement," according to Prof Ball.
In 1998, the doctor led a study that linked the MMR vaccine to autism, impacting on the coverage of the vaccine, with rates dropping to about 80% in the late 1990s and a low of 79% in 2003.
Rates partially recovered after the research was disproved but the volume of anti-vaccine sentiment on social media has increased in recent years.
This led Health and Social Care Secretary Matt Hancock to call for new laws to force social media companies to remove content that promoted false information about vaccines.
Prof Ball said there were rarely "side effects" with vaccines and even if there was, the benefits outweighed these.
"Because we have lived through a golden age of vaccination, we have forgotten just how harmful, and sometimes even fatal, these virus infections can be," he said.
Are students and others still at risk?
Dr Natalie Riddell, a lecturer in immunology and ageing at the University of Surrey, said a reduced amount of people being vaccinated against any contagious disease was dangerous.
"Babies and immuno-compromised people [such as the elderly or those receiving chemotherapy] rely on the rest of us to be vaccinated to prevent the spread of disease," she said.
"It is totally unnecessary for people to risk their friends and family becoming ill, or even dying, from measles or mumps, as there is a safe and effective vaccine to protect against both."
Prof Ball said poor vaccine uptake worldwide had led to an increase in outbreaks of mumps and measles and we should "expect things to get worse" before they get better.
A man who was stabbed to death inside his car in south-west London was the victim of a "vicious and targeted" attack, police have said.
The 40-year-old driver was knifed multiple times by three men as he was turning onto Clapham Park Road, near Clapham Common Tube station, on Friday.
The victim died at the scene and his next of kin have been informed, Scotland Yard said.
No-one has been arrested in connection with the killing.
Det Ch Insp Paul Healy said: "This was a vicious and targeted attack on a man inside his car in a busy area."
The force is trying to track down three male suspects, "all of slim build", who were seen leaving the area immediately after the attack at about 14:30 GMT, he added.
The Met also urged any witnesses or people with dashcam footage to get in contact.
There have been 22 fatal stabbings in the capital this year so far.
Campaigners said the move was "disappointing and regressive" and that stop and search is "not effective".
Stop and search powers have been controversial for many years, with evidence that they are frequently misused and that they target black people disproportionately.
But Mr Javid said: "The police are on the front line in the battle against serious violence and it's vital we give them the right tools to do their jobs."
The change is being trialled in seven police force areas where more than 60% of knife crime occurs: London, the West Midlands, Merseyside, South Yorkshire, West Yorkshire, South Wales and Greater Manchester.
It makes it easier to use so-called "section 60" searches, where officers can search anyone in a certain area for a limited period of time to prevent violent crime
Under the new rules, inspectors will be able to authorise the use of section 60; currently, more senior officers have to give approval.
There will also be a lower threshold for authorising searches - police will only need to reasonably believe serious violence "may" occur, not that it "will".
Other powers which account for the majority of searches will remain the same, and will still require officers to have reasonable suspicion of an offence.
Metropolitan Police Commissioner Cressida Dick said officers in London had increased the use of section 60 over the past 18 months, following 132 deaths from stabbings in the capital during 2017-18.
She said: "Stop and search is an extremely important power for the police. It is undoubtedly a part of our increasing results suppressing levels of violence and knife crime."
But Katrina Ffrench, chief executive of StopWatch, which campaigns against excessive use of stop and search, said: "This decision is a disappointing and regressive move, which is about politics not saving lives."
Removing the need for reasonable suspicion "will not only exacerbate the racial disparity, but has the potential to further damage the relationship between the black community and the police," she said.
In order to reduce violent crime by 2% in a borough during the following week, police would need to carry out 200 times the number of weapons searches, it said.
The extra powers roll back a key change made by Prime Minister Theresa May in 2014 when she was home secretary.
She introduced a revised code of conduct after an inquiry examined thousands of police searches and found 27% may have been illegal.
When misused, stop and search was "an enormous waste of police time" and "an unacceptable affront to justice", she said.
Reflecting on the recent announcement, the prime minister said the powers were "an important tool in the fight against knife crime".
Partly as a result of the 2014 changes, the use of stop and search fell in England and Wales from a peak of 1.4 million ten years ago to 277,378 last year.
The numbers of searches fell for every ethnic group, but ethnic and racial inequality has grown. In 2014-15 black people were four times as likely to be searched as white people, while in 2017-18, they were 9.5 times as likely to be searched.
Facebook Chief Executive Mark Zuckerberg called on Saturday for regulators to play a “more active role” in establishing rules that govern the internet, as the world’s largest social media network struggles to defuse criticism.
Zuckerberg, whose company is under pressure for failing to adequately police content and protect user privacy on its platform, wrote in a Washington Post article that a “standardized approach” for removing content would help keep internet companies “accountable.”
“By updating the rules for the Internet, we can preserve what’s best about it - the freedom for people to express themselves and for entrepreneurs to build new things - while also protecting society from broader harms,” Zuckerberg wrote.
His comments followed a Washington Post report saying the U.S. government and Facebook were negotiating a multibillion-dollar fine settlement over the company’s privacy lapses.
Zuckerberg also called for updated legislation focused on protecting elections, including new rules aimed at online political advertising that “reflect the reality of the threats” faced by social media companies.
U.S. intelligence and law enforcement agencies say Russian internet trolls helped spread divisive content and disinformation on Facebook in the run-up to the 2016 U.S. presidential election.
The time may come when Britain’s opposition Labour Party has to call another vote of no confidence in Prime Minister Theresa May’s government, the party’s foreign affairs spokeswoman Emily Thornberry said on Sunday.
May’s government survived a vote of no confidence in January, the day after her Brexit deal was rejected for the first time. It has been voted down two further times since then.
When asked if Labour would put forward another no confidence motion, Thornberry told Sky News: “We shall see. I mean obviously it does look like time may come when we will need to call another confidence motion.”
Thornberry also said it was “likely” Britain would still pursue the policy of leaving the EU if Labour was in government.
Political reporter(wp/reuters)::: British Prime Minister Theresa May risks the “total collapse” of her government if she fails to get her battered Brexit deal through parliament, the Sunday Times newspaper said, amid growing speculation that she might call an early election.
Underscoring the tough choices facing May to break the Brexit impasse, the newspaper said at least six pro-European Union senior ministers will resign if she opts for a potentially damaging no-deal departure from the EU.
But at the same time, rival ministers who support Brexit were threatening to quit if May decides to stay close to the EU with a customs union or if she sought a long delay to Brexit, the Sunday Times said.
May’s Brexit strategy is in tatters after the exit deal she hammered out with other EU leaders was rejected for a third time by the House of Commons on Friday, the day that Britain was supposed to leave the bloc.
Nearly three years after Britons voted by 52-48 percent to end the country’s EU membership after 46 years, what Brexit will look like or whether it will even happen remains up in the air.
May now has less than two weeks to convince the 27 other EU countries that she can break the deadlock. Otherwise she will have to ask the bloc for a long extension or take Britain out of the EU on April 12 with no deal to soften the economic shock.
May has said she will step down if her Brexit deal gets through parliament, offering her critics the chance of a different prime minister to lead the next round of negotiations with Brussels about Britain’s future ties to the bloc.
But that last-gasp offer has failed to break the impasse, leading to talk of an election.
The Mail on Sunday newspaper said May’s advisors were divided over whether she should call an early election if she fails to win support for her Brexit deal from parliament in the coming week.
The newspaper said a possible “run-off” vote could take place on Tuesday in parliament between May’s deal and whatever alternative emerges as the most popular from voting by lawmakers on Monday.
That meant an election could be called as early as Wednesday, the newspaper said, without citing sources.
An early election would need the support of two thirds of members of parliament, and the Observer newspaper said Conservative lawmakers were reluctant to let May lead them into another election after she lost their majority in 2017.
The Sunday Telegraph said senior members of the Conservative Party did not want May to lead them into a snap election, fearing the party would be “annihilated” at the polls if she faced down parliament over Brexit in the coming months.
An opinion poll in the Mail on Sunday gave the opposition Labour Party a lead of five percentage points over the Conservatives. That lead fell to three points if voters were offered the chance to vote for a new group of independent lawmakers who have not yet created an official party.
One of the most popular alternatives among lawmakers, including Labour members, is Britain staying in a customs union with the EU, an option also favoured by many business leaders.
Brexit supporters say a customs union would deny Britain the opportunity to strike trade deals around the world.
Earlier on Saturday, one lawmaker said Conservative members of parliament had written to May telling her to lead Britain out of the EU in the coming months, even if it means a potentially damaging no-deal Brexit.
The Sun newspaper said the letter was signed by 170 of the 314 Conservative lawmakers in parliament, including 10 cabinet ministers.
