African swine fever – a viral infection that causes the animals to bleed internally – is sweeping a country that has more pigs than people.
At least 13 wild boars have tested positive for the virus in fields outside Barcelona, in Spain’s northeast Catalonia region, since November.
The highly contagious illness, which is not fatal to humans but can be spread by us, has no known vaccine or cure.
What is behind the outbreak of the virus in Cerdanyola del Vallés is unclear, but officials are considering whether it leaked from a laboratory.
Officials initially suspected it was caused by a boar eating infected pork, such as a half-eaten pork sandwich tossed aside by a trucker.
Should the UK be worried about African swine fever?
Many in Spain, one of Europe’s largest pork producers, are keen to avoid a repeat of a 2018 outbreak in China that decimated pig herds.
The disease wiped out roughly one-quarter of the world’s pigs, or 220 million, according to Rabobank, an agricultural-focused bank.
Just two years later, the virus was confirmed in Germany, home to one of Europe’s largest swine herds.
Could a rogue pork sandwich left on the side of the road also cause an outbreak of swine fever in the UK?
More than 4.7 million pigs call British farms home, with millions slaughtered every year.
The Department for Environment, Food and Rural Affairs confirmed to Metro that African swine fever has not been reported in the UK.
And it will unlikely make the jump over the English Channel anytime soon.
Defra said: ‘We take the threat of animal diseases extremely seriously and our commitment to maintaining the country’s biosecurity is unwavering.
‘Following an outbreak of African Swine Fever in Spain, all fresh pork and other impacted products from the region affected are restricted. Exports from disease-free areas of Spain can continue as normal.
‘We will continue to monitor the situation and keep all measures under review.’
What is the cause of the outbreak in Spain?
Agriculture officials say the strain of African swine fever in the boars is similar to one first detected in Georgia in 2007.
The ministry said on Friday that the strains being similar ‘does not rule out the possibility that their origin may lie in a biological containment facility’.
Catalonia’s top agriculture official, Oscar Ordei, said an investigation has been launched into the Centre for Research in Animal Health (Cresa).
Cresa is just 1km away from where the dead infected boars were found.
A spokesperson told the fact-checker Maldita.es that it has found ‘no evidence’ the virus leapt out of its lab.
Veterinary authorities found no traces of African swine fever at any of the 39 pig farms located within a 20km infected zone.
But with no known cure, pork dealers and butchers are calling for the some 30,000 pigs in the area to be culled.
Spain has deployed more than 100 army troops to help wildlife rangers curb the spread, while hunters have begun to comb the zone.
The country’s pork market is worth around €8.8 billion (about £7.7 million) a year.
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