Dáil Éireann debate -
Wednesday, 3 Feb 1999

Vol. 499 No. 4

Written Answers. - Blood Donations.

Liz McManus

Question:

134 Ms McManus asked the Minister for Health and Children if arrangements are in place to ensure that women who received contaminated blood or anti-D and were tested negative do not participate in giving blood in view of the risk in terms of faulty testing, masking of results by steroids and so on; and if he will make a statement on the matter. [3008/99]

Minister for Health and Children (Mr. Cowen)

My Department has raised the concerns of the Deputy in relation to the risk of faulty testing and masking of results by steroids with the Blood Transfusion Service Board. My Department is informed that the BTSB currently tests for HIV, HTLV-1/2, hepatitis B, hepatitis C and syphilis, using standard validated methods. The range of tests are as comprehensive as any in Europe and conform to existing international standards.

The enzyme linked immunoassay, ELISA, tests used by blood transfusion services are extremely sensitive tests which detect hepatitis C infection in blood donors. These tests are automated and the only instances where the test will not detect hepatitis C infection in blood donors occur when individuals are in the early phase of infection before antibodies develop, which can take up to 66 days. This period is called the window period and to exclude any possibility of such donors donating, blood transfusion services internationally, including the BTSB, do not permit recipients of blood or blood products to donate for a year after administration. After that period they are again acceptable as donors if they fulfil the stringent health criteria in place for donation and test negative for the above viruses. Since the individuals referred to by the Deputy were exposed to anti-D, which had the potential to transmit infection between five and 20 years ago, the concern about failure of testing due to the window period donations does not arise.

The actual residual risk, even for a donor donating in the window period, is extremely low and in Ireland has been calculated to be 1: 500,000. To further exclude this possibility, the BTSB in line with other transfusion services is in the process of evaluating and introducing new technology in association with the Scottish National Blood Transfusion Service to detect such donors. My Department has made the necessary funding available for the introduction of such sophisticated technology which is called polymerase chain reaction, PCR. Extensive experience in Germany and Scotland with PCR testing has shown that apart from donors in the window period mentioned above, immunosilent donors, that is, donors who are infectious but are negative for HCV antibody, have not been found.

The donor questionnaire which blood donors complete prior to donating includes,inter alia, questions as to whether the individual has attended a doctor in the last 12 months and whether he or she has been admitted to hospital or had medical investigations/surgical procedures as an outpatient in the previous 12 months. Further questions concern whether he or she is receiving any form of medical treatment and whether he or she is feeling well and healthy. Potential donors are also asked whether they have ever used a needle – even once – to take any drugs, including body building steroids. Therefore, individuals who could be immunosuppressed or who are on drugs, such as steroids, which interfere with the immune system are not acceptable as donors. These deferral criteria are under constant review and conform to the highest international standards.