Health officials are 'particularly concerned' about those who attended Temple Street Children's Hospital on a number of dates
The HSE has confirmed five further cases of measles - bringing the total number of cases in a recent outbreak to 11.
Cases have been reported in children and adults who are in contact with others who have had the disease in the community in Dublin.
However, the HSE says it is 'particularly concerned' about the risk of those who attended Temple Street Children's Hospital on a number of dates in recent weeks.
Both adults and children who attended the hospital on the four dates in question and who have developed symptoms are being urged to stay at home and phone their GP for advice.
The risk of measles lasts for up to 21 days after contact.
Symptoms of measles include a high fever, runny nose, red eyes and a red rash that 'starts on the head and spreads down the body'.
Dr Helena Murray, specialist in Public Health Medicine, explained: “Measles can be a serious illness and is highly infectious.
"The best protection is to be fully vaccinated with two doses of MMR (Measles, Mumps, and Rubella) vaccine.”
According to the HSE, there are ongoing outbreaks of measles both in Europe and worldwide.
It is advised that young children aged under 12 months receive a dose of the vaccine before travelling to anywhere measles has been reported, while any adults or children who have not had their recommended doses are also being encouraged to get vaccinated.