Chronic consumption disease (CWD) infections occur in reindeer and moose in Norway.

A year after the deadly and highly contagious wildlife disease emerged in Norway, the country took action.
the disease, known as chronic consumption disease (CWD), has taken a devastating toll on deer and elk in North America.
CWD is caused by a protein called prion misfolding, which has cost hunting millions of dollars.
But the condition is the first in Europe for reindeer and moose in Norway, said Bjørnar Ytrehus, a veterinary researcher at the Norwegian Institute of Nature.
" Norway's agriculture and food minister recently gave hunters the green light to kill the 2,000 deer, which is equivalent to 6 percent of the country's wildlife, after three infected deer were found in a herd.
now we have to take action," said Karen Johanne Baalsrud, director of animal and plant health at the Norwegian Food Safety Authority in Oslo, 2015.
"to prevent secondary infections, the deer's habitat will be quarantined for at least five years."
success in eradicating the disease depends to a large extent on when CWD appears in Norway and begins to spread.
CWD was first discovered in 1967 in 24 U.S. states and two Canadian provinces, and the disease spread to other regions by transporting infected animals.
in deer, many species, including elk, moose and several other deer, are vulnerable to the virus.
infected animals often experience the following symptoms: weight loss, tiredness and drowsiness, drooling within 2 to 3 years of infection, and then death within a few months.
Ohio, CWD has been endemic for decades, with infections reaching 40 percent in some communities and white-tailed deer decreasing at a rate of 10 percent a year.
CWD is very contagious: the prion virus can be easily transmitted through saliva and excreta such as urine and feces, and it can survive in a normal environment for several years, suggesting that animal breeding stations and the salinization of animal rock salts have become the main sites for infection.
, a prion researcher at the University of California, San Diego, said that once the disease took root, it would be difficult to clean up the region's environmental pollution.
"So far there's no good way.
" Although there is no indication that humans will get any disease after eating infected veng meat, scientists still do not recommend eating (mad cow disease is also caused by the prion virus, human consumption of infected beef can be transmitted, so far mad cow disease has killed more than 200 people).
Norway's first case of CWD was stumbled upon by wildlife scientists working in the rugged mountains of the Nordfjella region: on March 15, 2016, they found a sick young reindeer that was tested by the Norwegian Veterinary Institute after its death.
I can't believe it," said Sylvie Benestad, a prion researcher at the institute.
" but then the International Reference Laboratory confirmed her diagnosis.
Benestad and colleagues found that the prion virus is similar to the virus in infected deer in North America.
so how did these viruses drift across the sea to Norway? It's still a mystery.
researchers say bottled deer urine sold on the market to catch animal bait may contain the virus, or it may have arrived with hiking shoes, travel boots or hunting tools.
but scientists have found that as proteins in a single individual begin to fold incorrectly, prion disease can also occur on its own, and Benestad's hunch that this spontaneous pattern is the most likely cause of cases in Europe.
the first case was detected, Norwegian officials began looking for other cases.
May 2016, a local hunter spotted two moose with CWD near a small town called Shibu, 40km southeast of Trondham.
during the last hunting season in the fall, thousands of hunters and volunteers from across the country collected about 8,000 brain samples, during which two infected reindeer brain samples were found, from near nordfjella.
Benestad said the Nordfjella area did not appear to have anything to do with the cases found in Shibu because reindeer and moose prions were not a type.
, the Norwegian Scientific Committee on Food Safety convened an advisory panel.
recently, the team gave different recommendations for cases in both places.
they recommend increased oversight around Shibu.
The two infected moose are too old, suggesting that they are less likely to be infected than cases of spontaneous disease (the reason is that in cases of spontaneous prion disease, such as sheep, prions are found only in their brains).
and even if they are infected, the animal's habit of living alone still reduces the chance of the virus spreading.
, the advisory group also warns that CWD may be lurking in every corner of Norway.
Norway will collect 20,000 samples during the next deer hunting season to test the health of deer herds across the country and continue to do so for years to come.
addition to this, the European Food Safety Authority has issued a report recommending that seven countries around Norway begin a three-year deer sampling program.
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