Cases of the potentially fatal disease mumps have quadrupled in Oxfordshire in the last five years.

The increase has prompted health experts to encourage parents to give their children the controversial MMR jab, which protects against the condition as well as measles and rubella.

However, there is no cure for mumps -- a viral infection.

A child with mumps, showing the swollen jaw and face Dr Karl Knox, an Oxfordshire consultant of communicable diseases, said county GPs reported 31 cases of mumps in 1999 -- about 15 every six months.

In comparison, Dr Knox's team has already been notified of 58 cases in the first six months of this year -- a 287 per cent increase. None of those affected has died.

He said: "What we are seeing in Oxfordshire is consistent with national statistics. It looks like its happening mainly to older children, but we don't know why this is.

"Children should continue to get the MMR jab. It's a safe and effective vaccine and this just emphasises its importance.

"There's no treatment for mumps and the MMR vaccine is the way to prevent it."

In recent years, many parents have stopped their children having the MMR vaccine, which some research has linked to the onset of autism and bowel conditions.

But Dr Knox said that parents opting out of the vaccine was unlikely to be the cause of the recent upsurge in mumps.

He added that cases of measles and rubella had not increased.

He said: "It's more complex than that. In Oxfordshire, the uptake of MMR is as good as, if not better, than the rest of the UK.

"Mumps, measles and rubella spread in slightly different ways. Although we have one good vaccine, the three diseases are individual organisms that all behave differently."