There have been more cases of mumps in the first 11 weeks of 2019, than all of last year.
The latest weekly report from the HSE has found there's been 593 cases of mumps so far.
Cases of the highly contagious disease have seen a rapid increase since the turn of the year, with outbreaks reported at some schools and universities.
Cases of mumps went over 70 for the third week in a row last week, with 71 people diagnosed.
204 of the cases were in the Eastern Region, with the lowest being reported in the Southern area at 16.
Over 60% of the cases reported came from those aged between 15 to 24.
The HSE is advising that the best protection against the disease is two doses of the MMR vaccine.