Aneurin Bevan, Monmouthshire's health board, is warning the county could be in a 'waiting game' to experience a measles epidemic like that seen in Swansea.

Director of Public Health Gill Richardson has described the uptake of MMR vaccinations in Monmouthshire as "very disappointing" and has named Monmouth and Caldicot comprehensives as having particularly low numbers of consent forms returned to the school.

Fifteen new measles cases have been recorded in the Aneurin Bevan Health Board area in the last two weeks according to figures released by Public Health Wales, bringing the total number of cases in Gwent in 2013 to 76.

Meanwhile, there has been a further increase in cases in the measles outbreak centred on the Swansea area, with 1,061 cases reported since the beginning of November 2012.

The greatest concern is for people aged between 10 and 18, the age group hardest hit in the current outbreak and most likely to have missed out on routine MMR vaccination in the late 1990s due to fears about vaccine safety.

One vaccination is known to provide 95 per cent protection, whereas the second boosts coverage to 98 per cent.

Data published last week revealed that almost 10,000 people in the Aneurin Bevan Health Board area between the ages of 10 and 18 are still unprotected from measles.

The disease is very serious, and in the latest epidemic has proven fatal. Those with a reduced immune system are most at risk, including those on high levels of steroids, those receiving treatment for cancer and Leukemia and those with HIV are extremely at risk.

Dr Richardson said: "Those not vaccinated are highly likely to catch measles, which is highly contagious.

"It is just a matter of time before a child is left with serious and permanent complications such as eye disorders, deafness or brain damage, or dies.

"Parents of young children appear to understand this well. The number who have contacted their GP or turned up at one of the many drop in clinics held in the last month has been very encouraging.

"Cases have increased in Gwent five-fold since November. We are possibly in a pre-outbreak situation with time to act, but there is still much to do.

"Vaccination sessions are continuing in schools across the Gwent area and I urge pupils and their parents to take advantage of these.

"We are already seeing cases in secondary schools in our area. Could I please urge parents and young people – please do not leave action too late to avert an outbreak here."

Further information on measles, including a link to a video testimony from a mother whose three year old unvaccinated daughter contracted measles, is available at: http://www.publichealthwales.org/measles">www.publichealthwales.org/measles

• A catch-up vaccination clinic will be held at Chepstow Community Hospital on Saturday 18th May and Royal Gwent Hospital (Main Outpatients).

Anyone can drop into the clinic and get an immunisation. The health board is particularly keen to target 10 to 18-year-olds.

Babies under 12 months cannot be immunised in this clinic, please contact your GP.