The Irish Blood Transfusion Service (IBTS) has started contacting thousands of regular donors, asking them to consult doctors to check if they are anaemic. The IBTS would cover associated expenses.

Owing to a defect in the equipment, low haemoglobin levels in donors apparently went undetected between July 2014 to November 2015. This means there is a high risk of people developing anaemia after donating blood. So far, the IBTS has contacted 90,000 regular donors.

What has made the issue more complicated is that women donors whose tests failed to identify that they already suffered from iron deficiency continued to donate. Consequently, IBTS has stopped accepting blood from all women, until the faulty equipment is replaced.

A helpline with additional staff has been set up to take calls from donors, an IBTS spokesperson said. People who donated blood between July 2014 and November 2015 are encouraged to use the helpline on 1850 731 137.

The IBTS has also sent the first set of letters to donors. The rest are to be covered in the next two weeks. The agency said it would seek compensation from the maker of the faulty equipment.