Iain Laurie, 23, from London, first noticed something might be wrong when the saliva glands either side of his face began to swell.
Iain had the puffy cheeks, typical of mumps
"I went to work and was feeling a bit iffy, but by the end of the day I felt pretty horrific," recalls Iain.
The next morning the doctor confirmed Iain's suspicion that he had caught mumps from his brother, Colin, aged 20.
Iain said: "My brother had caught it three weeks before at University.
"But he hadn't felt that ill, so I thought I would still hang around with him and didn't worry about it."
Unlike Colin, who recovered quickly from the virus, Iain was ill for about three weeks.
"I felt really bad, like when you have got flu - tired and aching.
"Eating and swallowing was really difficult and for some reason, everything seemed to taste of salt. It was horrible.
"All I could do was eat yoghurts and drink soup. I'll never touch yoghurts or drink soup again I don't think."
Iain said he followed his GP's advice and stayed in bed, drinking plenty of fluids and taking pain killers when needed.
Unfortunately, Iain developed one of the complications of mumps, swelling of the testicles called orchitis.
"It was painful as hell. That was the worst."
Rarely, this can lead to infertility. But, thankfully, Iain made a full recovery after more bed rest.
Iain said: "It was worrying, but I think other people were scared for me rather than me being scared for myself. It was a relief when I got better."
More and more people around Iain's age are coming down with mumps.
The Health Protection Agency says this is because they were born before the vaccine against measles mumps and rubella (MMR) became routine in 1988.
The government is urging people who have not been immunised against these diseases to consider having MMR.
Some higher education establishments have been offering special MMR sessions to protect these young people against mumps.
Iain said: "I had all the other things as a child, like measles and chicken pox, but I never had mumps, and never knew any other children with mumps.
"I fell in the wrong age group and missed out on MMR.
"I wish I had been vaccinated. It was the sickest I have ever been. I couldn't work for three weeks and lost a bit of money.
"I would sooner have been vaccinated and never had it.
"I'd also like to tell my brother what a swine he is for giving it to me. I haven't seen him since. I think he has been avoiding me," he said.