There has been an outbreak of mumps at both Trinity College and Blackrock College in Dublin.
The highly contagious viral infection causes pain and swelling in the cheek and jaw, serious fatigue and fever.
University authorities have warned students with the symptoms to stay home.
Blackrock's clash with St Michael's in the Leinster Schools Cup quarter-finals has been put off.
The HSE has warned anyone who has not had both rounds of the MMR jab they are "quite likely" to get mumps.