The number of measles cases has more than trebled in the past year, according to figures from the National Disease Surveillance Centre. The majority have been among young children.
Dr Joan O'Donnell, specialist in public health medicine with the NDSC, said there had been 533 cases of measles in the State in the 12 months up to July 26th, compared with 165 in the same period last year.
"It is shocking and the numbers will probably increase with epidemics at regular intervals if the uptake of the MMR vaccine does not increase," said Dr O'Donnell.
She added that the vast majority - 451 - of the past year's 533 cases were among children who had not been immunised: "343 were in the 0-to-4 age group and 108 were in the 5-to-9 group."
In May a Co Wicklow national school was forced to close because of an outbreak of measles.
Three pupils at St Philomena's in Bray fell ill. As few as 40 per cent of pupils in the youngest classes there were said to have had the MMR vaccine. Nationally the uptake of the combined MMR (measles, mumps and rubella) vaccine has increased slightly, said Dr O'Donnell. Some 75 per cent of 24-month-old children had received the combined MMR at the end of last year, an increase of 2 per cent on the previous year.
Immunisation rates increased in all the health board areas, except the North Eastern Health Board where immunisations fell by 1 per cent, the Mid-Western Health Board, where rates also decreased by 1 per cent, and the North Eastern Health Board where rates remained the same.
Although the national uptake is showing a slight increase, it is still 8 per cent lower than the rate recorded at the end of 2000 and 20 per cent behind the World Health Organisation recommended target of 95 per cent. And despite the recent slight increase, the rate here is well below levels in Britain where concerns have been widespread about the falling levels of immunisation.
In March, the Scottish Chief Medical Officer, Dr Mac Armstrong, expressed his concern that the rate of immunisations had fallen to their lowest level, 86 per cent.
Asked why parents were failing to bring their children for the MMR in sufficiently high numbers to ensure national protection, Dr O'Donnell said the main reason was "anxieties about the vaccine".
Concerns continue to centre on research published in 1998 by London-based Dr Andrew Wakefield which appeared to link the vaccine to the onset of autism.
Dr O'Donnell said the vast bulk of scientific evidence indicated that there was no danger from the vaccine. "It is safe and the risks from measles are far greater," she said. The risks include death, she pointed out, adding that during the 2000 epidemic in the eastern region, in which 1,500 people - mainly children - were infected, three children died. More than 100 children were hospitalised, she said. Other complications from measles include meningitis, pneumonia, encephalitis and convulsions. Mumps could also give rise to meningitis, encephalitis and deafness.
Dr O'Donnell said there should be improved communication about MMR between GPs and parents and more user-friendly means of accessing information about it.
She said there had been no studies into the safety of the single-dose vaccine, whereby children get six single-dose vaccinations over a long period rather than a combined vaccine at 15 months with a booster shot at four to five years.
