As many as 62 measles cases have been notified to health authorities in the first three months of the year, a 6,000% increase compared to a single case for the same period last year.

Only two of the 20 people infected with measles following an outbreak in Limerick city were vaccinated against the disease.

The number of cases of measles in Limerick has jumped to 20 since the start of the new year, including one linked case in Dublin.

The HSE has warned of likely further undiagnosed measles cases in Limerick city because one of the cases in the current outbreak has no obvious link to the other 12.