A measles and mumps epidemic could sweep through Sussex because not enough children are being protected against the diseases.

The percentage of children in Brighton and Hove given the triple measles, mumps and rubella (MMR) vaccination is one of the lowest in the South-East.

Just 55.7 per cent were given two doses of the jab by their fifth birthday, compared to the regional average of 72.3 per cent.

Only Newbury and Reading in Berkshire are lower, with rates of 52.2 and 54.8 respectively.

The rest of the nine primary care trusts (PCTs) in Sussex performed higher than the average, with Crawley reporting the best rate at 84.9 per cent.

However, the take-up is still significantly lower than the 90 per cent recommended by the World Health Organisation.

It says this is the level of protection a community needs against disease to reduce the risk of an epidemic.

The national average, according to figures released by the Chartered Society of Physiotherapy, is 73.3 per cent, with the North-East having the highest rate in the country at 80.4 per cent.

Angela Iversen, a consultant in health protection for Brighton and Hove City PCT, said: "MMR is a good safe vaccine used in many countries across the world.

"It is given at 13 months and as a pre-school booster at about four and a half years.

"It gives good protection against measles, mumps and rubella and I would strongly encourage people to make sure their children have it.

"Evidence of the safety of this vaccine is increasing all the time.

"You can make an appointment with your own GP to receive the vaccine or discuss it with your health visitor if you have any questions or concerns."

The low take-up rate is partly caused by research published in 1998 which generated widespread panic among parents when it suggested a link between MMR and autism.

This claim was rejected by the majority of experts, who insist the vaccine is safe.

However, there are still parents who are unwilling to let their children have the vaccination because of the perceived link.

Some have paid to have their child inoculated with single vaccinations instead but not everybody can afford the cost.

Mumps vaccinations were offered to all pupils at Mid Sussex secondary schools last year because of concerns a national epidemic had spread to the area.

All 16 to 18-year-olds were advised to have the jab.

Recorded cases of mumps increased from three incidents in 2003, and eight in 2004, to more than 60 cases in the first nine months of 2005.

A lot of teenagers around 16 to 18 had just the one routine MMR vaccination, whereas nowadays two jabs are given routinely for extra protection.