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20 Reasons why Asia has to fear ASF

African Swine Fever (ASF) has entered China and it is very likely that the outbreaks will have far-reaching consequences for the swine situation in Asia. Pig Progress editor Vincent ter Beek connects the dots.

In total, since the 1st of August, in less than a month 4 outbreaks have been reported on in China – in the provinces Liaoning, Henan, Jiangsu and Zhejiang province. That may not sound like a lot if you compare it to the spread of Porcine Epidemic Diarrhoea (PED) in the USA a few years ago or even the continuing reports of outbreaks of African Swine Fever (ASF) in middle and eastern Europe.

Every report by the World Organization of Animal Health (OIE) as well as Reuters mentions the determination of the Chinese authorities to deal with the challenge as quickly as possible and large amounts of culls are being reported in the direct vicinity around outbreak spots to avoid further spread.

Yet, there are a few reasons to be gravely worried that this is going to be much bigger – not only in China but also in the remainder of Asia. I hope I am wrong, but I don’t think so. Here is why.

 History of ASF in China

It looks like August does not constitute the onset of African Swine Fever in China at all. There is a serious study on the Web stating that the virus has been around in China since at least June and other sources even mention April. Even if stringent measures were taken after the discovery, it looks like the virus had the chance to spread through the country relatively ‘unnoticed’ for at least 2 months.

On top of that, the origin of the batch that was confirmed at the slaughterhouse in Henan province came originally from Heilongjiang province, close to Russia. For how long did the virus circulate there before it was picked up?

 The speed of the spread is worrying.

In Europe, to travel from Georgia to the Czech Republic, a distance of almost 3,000km, it took the virus 11 years, from 2007 until 2018. In China, however, the virus spread from Shenyang in northern China to Wenzhou, south of Shanghai, in about 3 weeks. That equals a distance of 2,100km.

 Look at the spread pattern in Europe.

In Eastern and Middle Europe, most of the outbreaks have followed a pattern of dissemination in local wild boar population, after which it mostly stayed local or creeped further. This is mostly because the ASF virus combines high mortality with a low contagiousness (it requires physical contact for the virus to transmit). What emerged was local wild boar populations being infected and the odd farm in the same region, but that outbreak zones hardly moved.

Rupinskai Farm in Lithuania was the 1st in the European Union that had to be completely cleaned out due to African Swine Fever. What remains is desolate emptiness. Photo: Vincent ter Beek
Rupinskai Farm in Lithuania was the 1st in the European Union that had to be completely cleaned out due to African Swine Fever. What remains is desolate emptiness. Photo: Vincent ter Beek

Every so often, the virus would pop up 500km down the road – most likely because humans took infected pork with them on their travels. So far, in Eastern Europe, the virus could not be stopped.

It looks like, what happened at a relatively slow pace in Europe, is now unfolding at enormous speed in China.

 China’s pig density.

Half of the world’s pigs are in China. That was around 457 million in 2016 according to data of the FAO. As 2/3 of China is either mountainous or desert, this amount of pigs can be found mainly in the eastern 1/3, sharing this space with 1.3 billion humans. Wherever ASF will be found, culling operations will always include many pigs.

In Russia, where ASF has been around since 2008, owners were asked to cull their own pigs. Photo: Shutterstock
In Russia, where ASF has been around since 2008, owners were asked to cull their own pigs. Photo: Shutterstock

 Still many backyard farms.

China, as often stated, is a country that is in transition. On its way to industrialisation and modernisation, people leave the countryside and move to the cities. It doesn’t mean, however, that all is already ‘converted’. Recently, Dr John Strak estimated in his overview that by the end of 2017, 52% of the Chinese herd was still in backyard farms. Huge developments – but this means that still half of the pigs in China are kept in backyard conditions.

Example of a very small scale pig farm in China. Photo: Henk Riswick
Example of a very small scale pig farm in China. Photo: Henk Riswick

 Many huge swine farms.

It follows that 48% are then kept in modern farms. Some of these are kept in farms modelled after European or American farms – in a large set-up and often on the principles of good biosecurity. The vast market has even invited the Chinese to build complexes that surpass anything seen in Europe or North America, like the multi-storey swine farms. What will happen if ASF will be confirmed near a complex like this?

Multi-storey pig farms, built recently near Guigang, southern China, to house 1,000 sows per floor. Photo: Henk Riswick
Multi-storey pig farms, built recently near Guigang, southern China, to house 1,000 sows per floor. Photo: Henk Riswick

 One policy covering all ASF?

As Prof Yang Hanchun pointed out mid-August in Science Magazine – the biggest challenge perhaps for the Chinese government is to implement one ASF policy that will cover all sections of the market, both backyard as well as developed swine farming. That will be a virtually impossible job given the sheer size of the country.

The understanding of the virus.

Which brings me to how the Chinese themselves deal with the virus. To put it bluntly, everybody who is dependent on pigs to make a living of course knows about any disease the animals can have. But how about families who have kept a few pigs on the side for centuries? Do they know about a virus that wasn’t officially present in China until 1 month ago?

The understanding of biosecurity.

Are these backyard farmers enough aware about biosecurity and the importance of it? When hearing about live pigs being transported from Heilongjiang province only to discover in Henan province that the animals were suffering from ASF, one can have doubts.

In addition, it wasn’t that long ago (2013) when many dead pig carcasses were found floating in the Huangpu river close to Shanghai – in what later turned out to be a mass collapse of the animals due to circovirus. Owners were afraid of the police and disposed of them in the water.

The weather doesn’t help.

To the element of biosecurity, another element can be added: that of nature. Just to illustrate, late August 2018, a huge typhoon called ‘Rumbia’ hit the Chinese east coast, with massive floodings as a result. The picture shows an affected greenhouse, but also swine farms have been affected with dead animals as a result. It only takes one infected swine farm and again carcasses can float from place to place.

A man in Guangdong province staring at his flooded greenhouse, late August 2018. Photo: ANP/EPA/Stringer China
A man in Guangdong province staring at his flooded greenhouse, late August 2018. Photo: ANP/EPA/Stringer China

Availability of diagnostics and laboratories.

Now let’s assume that much has changed for the better since then. And even if owners do realise it is better to ask for help when the pigs suddenly start dying – will the way be found to the right laboratories, one that can confirm it is the ASF virus?

Transparency of the Chinese authorities?

The paradox with open, transparent countries is that the more is being communicated about ASF outbreaks, the worse the situation appears – with potential negative trade consequences. Belarus, for instance, only reported 2 outbreaks of ASF in 2013 to the OIE – where all neighbouring countries had countless numbers of outbreaks. It remains to be seen how communicative the Chinese authorities appear to be. The rather unusual pattern of the outbreak (see points 2 and 3) suggests that perhaps more is going on than the authorities communicate.

Read more on pig health in the Pig Progress Health Tool

People complain on social media.

That thought is reinforced by messages on WeChat. Sources in China tell me that many Chinese people are complaining about the lack of information.

There are wild boar in China too!

China does harbour wild boar as well. Even stronger, modern-day pigs are most probably a result of breeding efforts of indigenous wild boar in China. That, in theory, is a reservoir for ASF to stay. Should ASF follow the same pattern as in Europe? I wouldn’t be surprised if wild boar are dying in China as well.

Ticks – the right climate.

Apart from wild boar, the virus can also be transmitted by (sub-)tropical soft ticks. Not a problem in Europe, as there it is too cold for this type of ticks. But in southern China, where the climate is warmer, that might be different. I’m told that China hosts over a 100 different species of ticks. Additional pig producing countries to the south of China (even more tropical!) also like pork.

ASF in food in South Korea.

Another important question is – what next? Late August the news broke in Korean media that customs had found pork in the bags of 2 travellers which contained ASF. In this particular case, the virus hadn’t reached pigs and was probably dead as the food had been heated.

Read more on South Korea’s pig situation in this analysis

South Korea, however, has the highest pig density of entire Asia, according to the FAO figures. It had better not have reached the country at all – reason to keep the border with North Korea as well as ports and airports tightly closed. That is why quarantine has already been tightened, according to news agency Reuters.

What’s going on in North Korea??

In terms of everything – North Korea is a black box. It is unclear how many pigs are being kept there, let alone in what conditions or what kind of diseases are around. Not an ideal situation if you want to prevent ASF from spreading.

Further south: South East Asia.

Further south, the situation does not look rosy either. Vietnam is known for its heavy predilection for pigs, but just as in China, the country is in full development, with modern, professional swine farms being built while at the same time pigs are brought to market on the back of a motorbike. From Wenzhou (south of Shanghai) to the border with Vietnam is only 1,800km. From what we have seen in the last month, the virus can be there in no time.

Pig production in Vietnam – what is it like?

Laos, Myanmar and Cambodia are also pig producing and consuming countries – but their levels of development are much lower even than Vietnam.

Thailand’s swine industry: well-developed.

South of that is Thailand – a country, on the contrary, with a highly developed swine industry and many pigs all over the country. The country is a lighting example for many producers all over Asia and a favourite tourist hub for many – this is where the world meets.

Agribusiness giants like Charoen Pokphand and Betagro, as well as others, are well-developed companies, which have even started phasing out sow stalls to indicate the level of development. Should ASF hit Thailand too, then the region’s major swine country is pushed back in its development.

Read more on the swine industry in Thailand

The unexpected…

The most vague one, I know, but African Swine Fever has surprised us in the past before. Who knows what kind of developments are around the corner.

Will the sea provide a good barrier to keep the virus out of Japan or the Philippines? Will the intensive travelling of this world’s population bring the virus to the Americas? And how is the development of a vaccine going now the world’s largest pig herd is affected? Will feed prices be affected? In China, the soybean futures are already falling due to ASF fears, according to Reuters. And last but not least, what will potential mass cullings mean for pig prices all over the planet?

One thing is sure – many more articles will follow on ASF. Unfortunately.

3 comments

  • Neil DeBuse

    There have been no real successes in Europe to contain ASF. That task would now seem to be incredibly easy, compared to the insurmountable task of "freezing" the spread of infection in a population of half the world's pigs. I cannot overstate how critical it is to be aggressive and transparent in battling this disease in China.

  • Vincent ter Beek

    Each continent has to learn how ASF behaves in their own context. In Northern and Eastern Europe, the disease has become endemic in wild boar, a situation that didn't happen before. Some experts believe the virus will become endemic in wild boar in many places in Europe, which emphasises the need for top-notch biosecurity. The level of success will depend on that.
    In China, they didn't know ASF either, but there apart from wild boar they have a lot of backyard farms and often no knowledge of ASF and/or biosecurity. Plus the information supply from China has virtually dried up. We'll know the real extent of the problems once it hits South Korea, Vietnam or Thailand.
    Out of curiosity: how will the US or Canada deal with the virus once it reaches North America?

  • J M Gibson

    In Asia there is a huge challenge in the fact that state veterinary services are weak and poorly administrated. Diagnostic facilities are poor and remote. In addition, there is not normally any incentive for any small backyard producers to report serious viral disease outbreaks (ASF, CSF,F&M) as they receive no compensation from the authorities for compulsory slaughter. The veterinary services are usually staffed with poorly qualified insufficient staff. In addition, corruption is rife at all levels within all government departments . Borders are porous - both state and provincial. It is not uncommon for small backyard producers to illegally move diseased pigs from a restricted zone to a clean zone. However, if the authorities in these one party countries - veterinary, police/law and order and legal - can implement strict viable blanket rules (in the same way they did with bird flu in Vietnam in conjunction with international veterinary support), then there is some hope. John Gibson

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