Missing documents meant it was impossible to link a specific contaminated blood product with a particular patient, writes Dick Ahlstrom, Science Editor
At least 252 haemophiliacs contracted either the AIDS virus or hepatitis C while receiving treatments provided by the Blood Transfusion Service Board (BTSB), according to the report of the Lindsay Tribunal, published yesterday.
The report indicates, however, that this is a "minimum figure".
The tribunal identified 252 men who had contracted either the AIDS virus, hepatitis C, or both, as a result of contaminated blood products supplied by the BTSB. Of these, 104 contracted the AIDS virus, HIV, and at least 217 contracted hepatitis C.
The tribunal faced difficulty establishing which particular product caused a particular infection.
A key task of the tribunal was to understand how blood products containing infectious viruses actually reached haemophiliacs being treated for this blood-clotting disorder.
The "state of treatment records" made it "impossible" to link a product with a particular patient, according to the tribunal.
"The difficulty in this regard was exacerbated by the fact that the despatch records of the BTSB [Blood Transfusion Service Board] in regard to relevant blood products had been destroyed in 1993, for reasons which remain unclear," it states.
Haemophilia is an inherited blood disorder mainly affecting males. The person does not produce certain "Factors", special blood proteins which promote the formation of blood clots. Without these factors, such as Factor VIII and Factor IX, haemophiliacs are in constant danger of bleeding to death from the smallest of injuries.
Treatments were developed, which involved the replacement of the missing factors by collecting them from blood and plasma donations. Blood from many donors was pooled and the scarce factors removed.
While this provided effective treatments for haemophiliacs, it also exposed them to any blood-borne diseases carried by donors, in this case HIV and hepatitis C.
Products produced here by the BTSB used only pooled donations from Irish donors.
It had been assumed that local donations would mean a very low risk of HIV or hepatitis infection, but in fact when testing of donors began several HIV positive donors were quickly identified, the tribunal reports.
Large-scale pooling in the US done by the drug company suppliers included donations from potentially dangerous sources, including prisoners and drug addicts.
These carried a correspondingly higher risk of infectivity.
The tribunal found that 104 haemophiliacs were infected with HIV as a result of receiving virus-tainted blood products, the figure provided in testimony by Mr Seamus Dooley, laboratory manager of the Virus Reference Laboratory at University College Dublin.
Of these, 95 haemophilia A patients were infected prior to January 1985 by treatments coming from companies outside the Republic.
Prior to this time, the products provided here were not heat treated as a way to remove viral contamination. Only two haemophilia A patients who contracted HIV received blood products prepared by the BTSB, the tribunal found.
At least two-thirds of the haemophilia A patients who became infected had already contracted the virus by the middle of 1983, and the remainder before the end of 1984, the tribunal states.
The remaining seven persons treated with products for haemophilia B all received Factor IX prepared by the BTSB.
Two infected batches were identified by the tribunal as the cause of the HIV infection, and these were issued from June 1985 through July 1985 and from July 1985 through October 1985.
These batches were prepared from blood donors who had not been screened for exposure to HIV, the tribunal reports. "They had not been heat treated. All seven persons who were infected had received treatment from one or other batch and in some cases from both."
The Virus Reference Laboratory at that time was the main centre for HIV testing but one of a small number able to test for hepatitis C infection.
It recorded 217 haemophiliacs who had contracted hepatitis C, but Mr Dooley told the tribunal that other test locations might also have detected the infection in haemophiliacs.
"The tribunal accepts this evidence and regards the figure of 217 persons as being less definitive than the figure of 104 persons with haemophilia infected with HIV.
"The tribunal regards the figure of 217 persons as a minimum figure."