Combatting Chronic wasting disease in Norway
Historisk arkiv
Publisert under: Regjeringen Solberg
Utgiver: Landbruks- og matdepartementet
Tale/innlegg | Dato: 12.03.2019
Chronic wasting disease (CWD) is a transmissible neurologic disease (TSE) affecting cervids. The infectious agent is known to be a prion, a normal protein that in this disease misfolds and destroys the brain. The development of the disease is slow and always fatal. Affected cervids show loss of body condition and altered behaviour. Contrary to other TSE like BSE and scrapie, CWD prion proteins are also found outside the neurologic system like body fluids, lymphatic tissue and excreta.
CWD is endemic in some parts of North America where the disease occurs in mule deer, white-tailed deer, elk and moose. There is no evidence that CWD can be transferred to livestock or humans.
CWD in Norway
In April 2016 CWD was detected in a free-ranging reindeer in Nordfjella in the mountains in the middle part of Norway. This is the first time that CWD has been found in Europe and also the first time that it has been found in this species in the wild anywhere in the world.
In an attempt to eradicate classical CWD in Norway, the competent authorities have culled the entire flock of wild reindeer in the affected part of Nordfjella.
The flock of about 2,000 animals was successfully stamped out by February 2018, and among these animals 19 cases of CWD have been confirmed. This corresponds to an occurrence of approximately 1%.
In addition to the affected reindeers in Nordfjella, a variety of CWD has been found in four mooses and one red deer in other areas. In these animals the disease is clearly different from CWD as described from North America and that found in reindeer at Nordfjella. This type is more similar to atypical scrapie and atypical BSE.
Since the detection of CWD in April 2016, Norway has sampled and analysed approximately 75,000 individuals from all over the country across the four species: reindeer, red deer, roe deer and moose. Classical CWD (the North American-like CWD strain) is not observed in wild cervids outside the Nordfjella area or in the semi-domestic reindeer population in Norway.
Zoonotic risk of CWD
The Norwegian Food Safety Authority considers that meat from cervids in Norway is safe to eat. This is based on current international knowledge and a report from the Norwegian Scientific Committee for Food and Environment states that they consider the zoonotic risk of CWD to be very low. As a precautionary measure all animals tested positive are excluded from the food chain.
Suggested safeguard measures from EU
In 2018, EU has proposed safeguard measures that prohibit the marketing of meat from cervids from a territory where CWD (regardless CWD type) has been confirmed, and that cervid meat from all other parts of Norway has to origin from animals tested negative for CWD. This safeguard measure is now postphoned until the European Food Safety Authority (EFSA) has revised all new scientific evidences and updated their opinion on CWD, with deadline 30th September 2019.
Norway propose a risk based regionalization, in the same way as it is done when controlling other animal diseases. In addition to a monitoring program, we propose to limit the requirement for CWD-testing of cervids to the Nordfjella-zone since classical CWD has only been found there.
Monitoring program in other countries
A monitoring program initiated by EU has been implemented in the Baltic countries, Sweden, Finland and Poland as from 2018. However, the program is small, since only 6,000 cervids over a three-year period are tested in each country. In Norway we have tested about 75,000 animals the last three years.
The Sami people
According to the proposed measures from EU if a moose or reindeer is found positive for CWD (either classical or atypical) in Finnmark County, no meat could be sent to the EU from the whole Sami area in Norway. This would have significant negative market effects for the whole reindeer meat market and could potentially wipe out the livelihood of these Sami villages. According to the existing knowledge, we do not see this measure as justified.
For centuries, reindeer husbandry has been a traditional way of life and an important livelihood for the Sami people in the Northern Scandinavia. The consequences of interrupting or seriously harming that activity on unsecure scientifically based knowledge would be devastating.
Contribute to fill knowledge gaps
We will continue our intensive monitoring of CWD to further improve knowledge and the documentation of status throughout the country. We also have several ongoing research projects that will provide essential knowledge for the best possible management of this disease. Projects include an understanding of the spread of CWD, the differences between different varieties of the disease in reindeer and moose, understanding the genetic prerequisites for infection in Norwegian animals and the development of an in-vivo CWD-test. We will continue the dialogue with EU and others to achieve risk-based measures.
Concluding remarks
Classical CWD is transmissible and atypical CWD seems to be spontanious. The risk management for these two types should therefore be different. In our opinion, it is quite possible that the atypical CWD would be found in a multitude of countries and areas, if they were subjected to monitoring as is done in Norway.
In our opinion barriers of trade should not be based on unsecure information of the incidence of the disease. 6,000 animals tested in three years is few. We find it hard to accept that the finding of CWD in Norway may result in barriers to trade when so little is done to clarify the CWD-status in other countries.
The proposed safeguard measures means that one do not trust the tests performed, since no meat from large areas around a positive case can be placed on the market, even if the animal has tested negative. General measures restricting the placing of cervid meat on the market does not seem approriate as the test for CWD has a high sensitivity. It is crucial that we trust the results of the approved tests performed, as we do for other TSE's. The TSE regulations are based on the principle that TSE tests are reliable.
Norway has made great efforts to eradicate CWD. And with the intensive surveillance, we have a good overview of the distribution of CWD in Norway.
Our goal is to confine and if possible eradicate CWD from Norway. We feel that we are doing an important jobb, not only for Norway, but also for the rest of Europe, in order to reduce the risk of this disease becoming established and spreading further to other countries.