Overall Strategy Blood Supplies in View of the BSE Crisis

The so-called BSE crisis has initiated an intensified discussion on the safety of blood derivatives among the population. Mrs. Ulla Schmidt, the Federal Minister of Health, has asked Prof. Dr. Johannes Löwer, President of the Paul-Ehrlich-Institut and Prof. Dr. Reinhard Burger, chairman of the blood working group and deputy director of the Robert Koch Institut to develop an overall strategy on blood supplies - after consultation with experts - in view of the variant of Creutzfeld-Jacob-Disease, which is spreading in Europe,. The report from this expert group has now been presented. "So far, no case of vCJD transmission by blood or blood derivatives has become known", says Prof. Dr. Löwer, "with the analysis carried out here, we meet the demands of the principle of preliminary risk prevention before such a possible risk occurs".

The attachment to the press release contains a short presentation of the essential statements and suggestions contained in the report.

In short, the experts suggest considering and discussing the following measures in keeping with the risk prevention principle:

1. Intensified use of research funds for developing test methods.
2. Optimum use of blood products, which means a more economical use of such products altogether.
3. Until a suitable test has been developed, a pure precautionary measure (risk prevention) could be to prevent the theoretical vCJD transmission through blood transfusion by excluding those individuals from blood donations who have themselves received blood transfusions before. This, however, would entail restricted blood supplies.
4. Encouraging blood supplies, e.g. by campaigns motivating the population to act as blood donors.

"The report referenced is also designed to inform the public. Our wish is that the debate will continue intensively, especially among the specialists", as Prof. Dr. Burger expresses it.

Attachment: Summary of the Essential Statements and Suggestions Contained in the Report:

1. Significance of the variant of Creutzfeld-Jakob Disease (vCJD)

Experimental findings reveal convincingly that the kind of vCJD which occurred in the UK, a neurodegenerative disease in human beings, is caused by the BSE pathogen. Exposure of humans to the BSE pathogen (primary route of infection) in all probability occurred through food which contained highly infective cow material (e.g. spinal cord), or were contaminated with such material. However, the risk of exposure was probably considerably higher in the UK than in other European countries. At present, there are approx. 100 cases of vCJD in the UK compared with 3 cases in France and 1 case in Ireland. However, it is probably just a matter of time before vCJD also occurs in other countries, including Germany.

2. Epidemiological Prognosis

If pessimistic assumptions are used, model calculations estimate that there will be up to 6,000 cases of vCJD in the UK by 2040. "Worst case" scenarios expect 300-600 cases each for Germany and France by 2040, caused by primary infections from food.

3. Other Routes of Transmission (Secondary Infections)

Up to now there have not been any indications for another route of transmission of the vCJD pathogen, i.e. from one human being to another (secondary infections). However, from the scientific point of view, it cannot be ruled out that vCJD transmission can occur through surgical instruments, human tissue (especially transplants), blood or blood derivatives. If this is possible, vCJD would persist among the human population for a longer period of time, even if primary infections were prevented through appropriate measures.

4. Transmission by Blood and Blood Derivatives

The report concentrates on the question of whether the disease could possibly be transferred through blood and blood derivatives. To answer this question, studies have been carried out in animal models, which, however, have revealed contradictory results. In certain cases, the spongiform encephalophathy pathogen can be detected in blood, however, in small concentrations. From a purely preventative point of view, the report referenced assumes therefore that the vCJD pathogen can also be found in human blood. Its transmission through blood plasma products (e.g. Factor VIII, albumin, fibrinogen), however, seems highly unlikely, since the pathogen is already largely removed during the manufacture of blood derivatives. So what remains is the possible route of transmission through cellular blood products for blood transfusion, e.g. erythrocytes, thrombocytes or fresh blood plasma.

5. Determination Tests

So far, there are no suitable tests for the detection of the vCJD pathogen in the blood of blood donors, even though very promising approaches have been pursued. However, when these results are available cannot be predicted.

6. Measures

The report discusses many suggestions which are now carefully scrutinised by the ministry:

1. Encouragement of the development of test procedures for blood donations

   The report suggests that research funds should be used primarily to further the development of suitable test procedures.

2. Optimum use of blood products

   An effective preventative measure for the reduction of a potential risk of transmission of pathogens (including vCJD) could be the avoidance of any kind of use of blood products which is not absolutely necessary. The smaller the amount of blood units transferred, the smaller the risk of infection (critical scrutinising of the indication). Besides, a more efficient use of blood products could further a more economical consumption of the latter. The initiative for an optimum use of blood products started by Germany in 1999 within the framework of the European Union should be continued.

3. Exclusion of blood donors

   Until a suitable test has been developed, a pure preventative measure (risk prevention) could be to prevent the theoretical vCJD transmission through blood transfusions by excluding those individuals from acting as blood donors who have themselves received blood transfusions before. Such a measure for the prevention of a possible further expansion of the pathogen would affect approximately 4% of the blood donors in Germany, which is a loss that according to the German blood collection services could not be accepted just like that , in view of the prevailing blood shortage.

4. Promotion of blood supplies

   The report suggests that before introducing the exclusion of persons who have received blood transfusions from blood collections, appropriate measures should be taken guaranteeing blood supplies in Germany for a long period. This includes the use of saving potential (optimum use) on the one hand and carrying out suitable promotion and motivation campaigns for recruiting blood donors on the other. The motivation campaign for blood and blood plasma donors initiated by the Federal Office for Health Information by order of the Federal Ministry of Health is to be intensified.

Another press release was issued by the Federal Ministry of Health can be found here.

More information issued by the Robert-Koch Institut direct or at the hompage of the blood working group at the RKI.

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