The latest official figures show there were 40 measles cases reported within a week recently, further indication of a "worrying" increase in the number of cases infecting young people in Dublin and the eastern region.
The total reported by doctors in the region for all of 1999 was 108 cases. The Eastern Regional Health Authority confirmed yesterday that 40 notifications were received in the week up to March 18th, mainly concentrated in an area north of the Liffey in Dublin, where there is a large outbreak at present.
The number of reported cases for the eastern region so far this year stood at 215 cases last weekend.
Such figures, however, are likely to be only a fraction of total cases in the community, according to medical experts.
Their concerns have been heightened by the fact that one in four Irish children, aged two, has not received an initial MMR vaccine, which protects against the potentially serious effects of measles.
Dr Rory Lehane, of the Irish College of General Practitioners, said the latest figures indicated a "worrying trend", with greatly increased risk of similar outbreaks spreading from the eastern region.
While the numbers being seen in Dublin were not being found in Cork, where his practice is located, one case was likely to lead to many more. Those aged between 15 months and 12 years were vulnerable.
A vaccination rate of more than 90 per cent among children is considered necessary for protection, he said.
A new vaccination campaign was initiated last week by the Irish Pharmaceutical Healthcare Association, with the support of the Department of Health and Children.
Public health doctors are targeting schools where a child has already developed measles by vaccinating all other pupils.
While measles cases usually cause relatively minor symptoms, complications are common, with middle-ear infections occurring in 10 per cent of cases and pneumonia in one in a 100.
Encephalitis occurs in one in 2,000 cases. In addition, children who have had measles are more likely to have ear infections, convulsions and to be hospitalised than immunised children.
An ERHA spokeswoman said they were also trying to contact parents where there was no record of vaccination and ensure boosters were given to older children who may have received the main vaccine at about 15 months.