The number of cases of mumps in the county has risen sharply, with Truro a particular hot spot.

Parents have been warned to be on their guard for signs on their children, with a campaign launched by the Health Protection Agency and the NHS in schools, colleges and at GP surgeries.

The number of notified cases in Cornwall so far this year is already approaching annual levels.

In the first 18 weeks of the year there have already been 134 cases notified – just 19 cases short of 153 cases in the whole of 2009.

There are concerns that people are missing out on the MMR (measles, mumps, rubella) vaccine.

The awareness campaign urges people in the area to check their immunisation history to ensure they are protected against mumps. The MMR vaccine can be given at any time after the age of 13 months and protects against measles, mumps and rubella.

Posters will be displayed in GP surgeries, schools and colleges and explain what to do if you have mumps and how long to stay away from school or work to help stop any further spread of mumps within the community. Lee Evans, from the Health Protection Agency in Cornwall, said: “We have seen a sharp rise in the figures this year. There is evidence that the disease is hitting two age groups the hardest – primary and junior school children and 16 to 25 year olds.

“The situation is widespread throughout the county with hotspots in the large towns – Penzance, Truro and the St Austell/Bodmin areas. That is why we are working closely with the schools and colleges to inform students about mumps and to explain why vaccination is important.

“However, it’s not just students who are at risk and we would urge everyone up to the age of 25 to consult their family doctors about having two doses of MMR vaccine if they are currently unprotected. MMR also gives immunity to measles and rubella.” Mumps is a serious infection which can cause painful inflammation and swelling of the salivary glands under one or both sides of the jaw and a fever and headache.

Complications can include inflammation of the pancreas, viral meningitis (inflammation of the brain), inflamed and swollen testicles in men and ovaries in women and also deafness.

James Bolt, associate public health specialist for NHS Cornwall and Isles of Scilly, said: “The most effective way of preventing spread of mumps is through immunisation. We know there has been concern among parents about allowing their children to have the MMR vaccine but we are encouraging GPs to discuss these concerns with them to improve the take-up.

“Young people who have missed out thus far – including teenagers who may have had single vaccines for measles and rubella only – can also have the MMR vaccine free of charge. Anyone with such symptoms is urged to contact their GP as soon as possible.”

MMR vaccine can be given irrespective of a history of measles, mumps or rubella infection.