Masterstudiengang "Drug Regulatory Affairs"
Master-Thesis
The Etiology of BSE and Variant Creutzfeldt-Jacob Disease in Context with the new European Legislation for Material of Animal Origin, Commission Regulation (EU) No. 722/2012 Regulatory and Scientific Experience after the first BSE/vCJD Outbreak ***
Karin Hoffmann (Abschlußjahr: 2013)
Summary
Language: English
During evolution parasites and hosts are always playing the well-known cat and mouse play of measures and countermeasures at attack and defenses. Since time immemorial zoonoses threaten the health of humans (the most dreaded: pest and influenza, which extinct in each case nearly one third of the total human population in Europe) and the immune system of humans is fighting against different pathogens (viruses, bacteria, parasites, fungi, helminthes).
With BSE, its corresponding disease in humans (vCJD) and other TSEs (e.g. Scrapie: sheep), a new form of zoonosis was identified: the infectious agent is a degenerated protein, so called prion, (PrP), which is, in the normal form, also present in healthy humans. Hence the immune systems of animals and humans have no chance to fight effective against the PrP.
The first BSE outbreak in cattle in the eighties was caused by feeding ruminants with Scrapie contaminated meat and bone meal and several countries /regions worldwide were affected by this crisis. As in UK the first cases of a new variant of Creutzfeldt - Jakob disease (vCJD) in humans were published, scientific investigations identified the same prion protein, which causes BSE in cattle, in such patients. Hence BSE was classified as zoonosis and it was clear, that the disease can threaten human health causing vCJD mainly transmitted by PrP-contaminated beef food. Therefore several legislations come into force for minimizing the risk of TSE transmission by food. The most important are Regulation 999/2001 and Regulation 1069/2009.
At this time also specific legislation were introduced for health care products (medical devices and medicinal products) utilizing material from animal origin with the objective to protect public health by minimizing the risk for TSE infections by such products. One of these legislation, the Directive 2003/32/EG is recently replaced by the Regulation (EC) No. 722/2012, coming into force in August 2013. The existing provisions described in Directive 2003/32/EC, which includes manufacturer risk analysis and risk management of the animal material, have been updated in the new revision taken global experience into consideration. The most important changes are described in detail in this master thesis in conjunction with the consequences of all involved parties (manufacturers, NB and Member States). First of all, the changed legislation form, regulation instead of directive, can be noted. Both are legally binding acts, but regulations are directly binding to all EU Member States and must not be translated into national law. Furthermore a greater percentage of medical devices (AIMDs, custom-made devices and clinical trial materials) are now controlled by precautionary measures set in the Regulation (EC) No. 722/2012.
Why is there a revision of the legislation at this time point when BSE recently is no more a dominant public threat?
There is still a great concern worldwide that this fatal disease can re-circulate and scientific / regulatory experts recommend that the taken measures should not be decreased for several reasons, which were discussed in this master thesis. One of the reasons is the difficulty in calculation of risk for vCJD transmission because several people can carry the infectious agent without showing clinical symptoms. The unknown incidence of such `silent` carrier, the long incubation period and the lack of experiences due to the rarity of vCJD disease make calculation of the vCJD risk nearly impossible. In addition, so far there is no reliable diagnostic assay available, which can be used as screening tool to detect PrP in e.g. blood. Global CJD surveillance program revealed the main transmission pathways for PrP from human to human by blood and plasma products, which are in general applied intravenously and therefore have a great potential of transmission of pathogens, by organ transplantations (Dura Mater and Cornea) and by surgical interventions using contaminated medical devices (neurosurgical instruments). With this knowledge, attention must be paid for the future in further regulatory framework to minimize the risk for PrP infections especially by contaminated instruments during surgeries, which is recently handled different in each Member State.
Pages: 52