Pigs on a farm in Linquan county, Fuyang, last year, after African swine fever was confirmed in China (Photo: VCG/VCG via Getty Images)

African swine fever is seriously scary: here’s why you should care

Welcome to the Cheat Sheet, a clickable, shareable, bite-sized FAQ on the news of the moment. Today, it’s all about African swine fever and the pending aporkalypse.

TL;DR: It’s “the biggest animal disease outbreak the planet the planet has ever faced”, and Kiwi pork lovers need to do their bit to protect our local pigs.

African swine fever – wasn’t that the flu we were all scared of getting 10 years ago?

Nope, totally different things. African swine fever (ASF) is a viral illness that can only infect pigs – it poses absolutely no threat to humans. The swine flu pandemic in 2009 was the H1N1 or H3N2 virus, sometimes called Influenza A, which was first transmitted to humans by pigs around 20 years go. The illnesses aren’t related, other than both being viral infections.

ASF isn’t a new thing either: it first appeared in 1907 in Kenya. It was contained in Africa until the late 1950s, when it spread to Portugal and then had a few outbreaks in Europe up until the 1980s. Everyone thought it was pretty under control for a while, but over the past five years there have been lots of new outbreaks in Europe and Russia, and then in August last year it was confirmed in China.

Right, so what’s the big deal about China getting it?

The appetite for pork in China is massive – and half of the world’s pork production happens there. In 2018 they produced about 54 million metric tonnes of pork. And in the past six months, they’ve cut that production by 30% – about the equivalent of all the pork produced in the United States. It means that the entire world pork supply is about to be squeezed by increased Chinese import demand and decreased Chinese pork exports.

Hang on, what does ‘cut production’ mean?

Rabobank, which does a lot of work in the agro-economics space, reported in April that ASF has been confirmed in nearly every province in mainland China and affects between 150 and 200 million pigs. It’s hard to get a handle on what ‘affecting’ means, but it’s safe to surmise that an affected pig will either be showing signs of infection, or from a farm area where other pigs are showing signs of infection. Either way, those pigs are not long for this earth. Euthanising pigs is part of cutting production, and it also means those farms that have eliminated pigs won’t be in a hurry to fill up again.

Pigs infected with African swine fever are destroyed during an outbreak in Russia in 2009 (Photo: STR/AFP/Getty Images)

But if the virus can’t infect humans, why are the pigs being euthanised?

In short, because ASF is an animal welfare crisis. It doesn’t pass as rapidly as some other pig viruses, but once a pig has it… it’s pretty bad. There are three paths the virus can take – in its acute, and most common, form the pigs can experience high fevers, loss of appetite, internal bleeding, bloody diarrhoea and vomiting, coughing and laboured breathing – and after one to two weeks it’s basically unsurvivable. Sub-acute infections present with less severe symptoms, with mortality of between 30-70% of infected pigs within seven weeks, and any pigs that survive will remain contagious for the rest of their lives. Chronic forms of the infection are less common, and cause weight loss, fevers, coughing and skin ulcers – and again, surviving pigs are contagious for the rest of their lives. When a pig passes on the virus, what path it takes depends on the immune system of the freshly infected pig.

Yuck. So we don’t have this here in New Zealand, do we?

At this stage, no.

Great, so being an island in the South Pacific saves us again!

Not so fast. While ASF doesn’t spread between pigs as catastrophically as some other viruses, it is incredibly persistent in the environment and in contaminated pork, meaning we need to be looking pretty hard at what is coming across our border. MPI seems sure that the most likely biosecurity hazard is undeclared pork products coming in with travellers, and we need to make absolutely certain that no pig farmers are feeding their pigs food scraps to eliminate the risk of any infected pork coming into contact with our local pig population – including wild pigs.

It is not a massive threat for the commercial farms – their livelihoods are at stake so their biosecurity planning is already very strict – but for hobby farmers and wild pigs, it’s a real risk. A nightmare scenario is believed to have played out in Belgium, where pigs were infected after a traveller discarded a ham sandwich, containing ham from an infected pig, on the roadside, and it was found and eaten by a roaming pig, starting an outbreak that has almost ruined their local pork industry.

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What can non-farming New Zealanders do to keep our local pigs safe?

The most straightforward answer is this: only buy pork farmed in New Zealand. We know our herd is disease free, but despite MPI’s best assurances, no one can put their hand on their heart and say infected pork is not crossing the border. Australia has intercepted infected pork at its border, but we don’t have information from local authorities about what they are testing that has been picked up here.

Lots of New Zealanders are rightly appalled by many aspects of industrial-scale factory farming, but this welfare issue dwarfs the misery of intensive practices for pigs. If we don’t take action to keep our local pigs safe, it doesn’t matter how they are farmed, they will suffer.

This content was created in paid partnership with Freedom Farms. Learn more about our partnerships here


The Spinoff’s food content is brought to you by Freedom Farms. They believe talking about food is nearly as much fun as eating it, and they’re excited to facilitate some good conversations around food provenance in Aotearoa New Zealand.


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