There are 10 possible cases currently under investigation.
A possible case of measles is under investigation in the Dublin Midlands region.
The Health Protection Surveillance Centre has also confirmed there are nine cases of the virus in Ireland, and one outbreak.
The HSE is investigating 10 possible cases in the country - one in the Dublin Midlands region, four in Dublin North East, four in Dublin South East and one in the South West.
There's been one fatality as a result of measles this year, after a man in Westmeath died last month.