Scotland confirmed a case of mad cow disease Thursday but authorities are unsure whether the animal developed the illness in a one-off genetic mutation, or whether a more worrying underlying factor such as contaminated food was involved.
Scottish government spokesman Luke Boddice said a 4-year-old cow had died on a farm in Aberdeenshire, in the northeast of the country, and authorities discovered that it had contracted mad cow disease after a routine check.
“We are chasing its cohorts and will be destroying them in line with EU regulation in the coming days,” Boddice said, referring to other cows in the vicinity.
Also known as bovine spongiform encephalopathy, mad cow disease is an incurable disease that wastes the brains and nervous systems of infected cattle, causing muscular twitching or even frenzy. Scientists also believe that humans who eat BSE-infected meat can contract Variant Creutzfeldt–Jakob disease (vCJD), a fatal brain disease.
Britain was the epicenter of a mad cow disease outbreak during the 1980s and 1990s, which led to a Continent-wide food safety crisis and, eventually, to the creation of the European Food Safety Authority (EFSA) in 2002.
A European Commission spokesperson also said she thinks the case is a sporadic one.
However, the crisis also triggered global trade bans — the effects of which meat exporters still feel today. Brussels banned all British beef exports between 1996 and 2006, for example, while major importers such as China and the U.S. unilaterally blocked all EU beef exports. Both countries have only recently begun lifting these bans. Beijing only signed off on British imports in June; and it lifted its ban on Dutch veal only on Wednesday.
Still, both Edinburgh and Brussels are adamant that the recent case is an isolated one. Scotlands Rural Economy Secretary Fergus Ewing said he has imposed a ban on transporting cattle from the farm as a precaution.
Mad cow disease comes in two types. The first, “classical BSE,” can infect cattle through infected food. Investigations suggested BSE-infected cattle feed — containing protein particles known as prions that cause brain proteins to fold in on themselves — caused the the British outbreaks of the 1980s and 1990s. This led to an EU-wide ban on feeding processed meat to livestock.
In rare cases, however, cattle can also develop the disease sporadically. This is known as “atypical BSE.” Boddice said that Scottish authorities are now determining whether it was “a random mutation or it was some external factor” that caused the death of the cow in Aberdeenshire.
EFSA Executive Director Bernhard Url said there is no immediate reason to suspect that the infection came from infected feed. “We know that there are — very rarely — but there are sporadic cases of BSE. It can happen on a sporadic basis,” he said. “I would be cautious.”
A European Commission spokesperson also said she thinks the case is a sporadic one. “Its not like it didnt happen for the last 10 years,” she said, referring to a French case from 2016.
However, one of the main consequences of the case is that Scotland could lose its “negligible” risk status for mad cow disease, awarded by the World Organization for Animal Health (OIE).
The OIE said that downgrade is not automatic, and that it could not comment on the next steps.
Since the Brexit referendum, British beef exports have been boosted by the relative weakness of the pound. The main export destinations are Ireland and the Netherlands.
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