It's understood a case of rubella has been discovered at Apple's Hollyhill campus.
The Echo reports the tech giant confirmed to staff that a case of the disease was discovered there, however the HSE said it cannot reveal where the case was found due to patient confidentiality.
Rubella can cause a fever and distinctive rash and is usually a mild condition, although it can harm an unborn baby.
It's understood the discovery is the first confirmed case of rubella in Ireland in over a decade.