The Irish Blood Transfusion Service says it expects to lose five per cent of its donors after being forced to introduce new measures to reduce the risk of variant CJD.
The measures are being introduced after Britain confirmed last December the probability that the fatal disorder, known as 'Mad Cow' disease, was transmitted by blood transfusion.
The IBTS said it will now no longer accept blood donations from people who have spent 3 years or more in the UK between 1980 and 1996 or from donors who have received a blood transfusion in the Republic of Ireland on or after January 1st 1980.
It will also not use blood for transfusions for neonatal patients from donors who have spent more than 12 months in the UK.
Dr William Murphy, National Medical Director, said the new regulations would affect nearly five per cent of current donors.
"We still need to collect 3000 donations per week to ensure that we can supply hospitals with the blood necessary for patient care," he said, and urged anyone who had not donated before or who had not donated recently to become a blood donor, if they fulfill the acceptance criteria.