CWD: New prion strains have been demonstrated in moose and reindeer in Norway

By inoculating mice with the prion strains found in cervids in Norway, a group of researchers has found that these are not identical to strains found in cervids in North America. These findings can be of great importance for how to manage the disease in cervids in Norway.

Chronic Wasting Disease (CWD), in Norwegian called “skrantesjuke”, is a prion disease identified in the late 1960’s in North America and its slow spread across the continent has been unstoppable. Since 2016, the disease has been detected in reindeer, moose and one red deer in the Nordic countries (Norway, Sweden, Finland).

REIN PÅ BEITEshutterstock_526814266web.jpg
Photo: Shutterstock

The prions that have been detected in Norwegian moose were in 2018 described as hitherto unknown prion types (Pirisinu ref). The results of a bio-assay study, which are now published in the prestigious PNAS journal, confirm that these moose were infected with previously unknown prion strains.

In addition, the study found that the prions in the Norwegian wild reindeer were not identical to the strains identified in North American cervids, even if they show many similarities.

The published article is the result of a long-term collaboration between the Norwegian Veterinary Institute, the Institute Superior of Health (ISS) in Rome (IT), the Canadian Food Inspection Agency of Ottawa (CA) and Colorado State University of Fort Collins (USA).

Use of bank vole

The characterization and comparison of the prions was possible thanks to the transmission of CWD-infection from cervids in Norway to a small rodent, known as bank vole (Myodes glareolus). This is a species that is very susceptible to prion diseases and is therefore well suited for such studies. When it comes to classifying different prion strains, inoculation of bank vole, along with genetically modified mice, is the most important tool.


Importance for how we manage the disease

The results show that in Norwegian cervids there is a variation with different strains of CWD prions.

-Since the newly identified prion strains have not previously been characterized, the information can be of great importance for how we manage the disease in cervids. This is especially true of moose strains, which do not appear to spread in the same way as wild reindeer strains. With new strains also comes the question of whether these can represent health risks for us humans, says Sylvie Benestad, prion researcher from the Norwegian Veterinary Institute.

Read the article: "Studies in bank voles reveal strain differences between chronic wasting disease prions from Norway and North America".

Sylvie Benestad

Senior forsker
Mobilnr: +47 97536830

Knut Madslien

Mobilnr: 4791736909

Jørn Våge

Seniorforsker vilthelse, skrantesyke/CWD-koordinator
Mobilnr: +47 93413615

Turid Vikøren

Vilthelseansvarleg / Veterinær
Mobilnr: +47 91648742

Linh Tran

Mobilnr: +47 97672367

Del artikkel