Photographer: Krisztian Bocsi/Bloomberg

The World Doesn’t Have Enough Pigs to Fill China’s Pork Deficit

Published: | Updated:

The deadly pig virus that spread from Africa across Europe and Asia will mean there isn’t enough pork in the whole world to make up for the millions of animals China is slaughtering to try to halt the contagion. But stopping African swine fever isn’t so easy.

The virus that causes the hemorrhagic disease is highly virulent and tenacious, and spreads in multiple ways. There’s no safe and effective vaccine to prevent infection, nor anything to treat it. The widespread presence in China means it’s now being amplified across a country with 440 million pigs—half the planet’s total—with vast trading networks, permeable land borders and farms with little or no ability to stop animal diseases.

Leaner Meat

China’s 2020 pig supply is projected to slump to a 27-year low

Number of pigs raised

800M

600

400

200

0

1994

2020

estimate

Number of pigs raised

800M

600

400

200

0

1994

2007

2020

estimate

Number of pigs raised

800M

600

400

200

0

1994

1996

1998

2000

2002

2004

2006

2008

2010

2012

2014

2016

2018

2020

estimate

Source: USDA

The estimated number of pigs China fattened in 2019 plunged about 30% to 490 million—the worst annual slump since the U.S. Department of Agriculture began counting China’s pigs in the mid-1970s. While the pig virus doesn’t harm humans even if they eat tainted pork, the fatality rate in pigs and the number of swine culled to curb the virus’s spread, mean it could destroy the region’s pork industry.

Pork is the staple animal protein in China. Rabobank expects domestic supplies to hit a low in the first half of 2020, as a result of an expected 25% drop in output in 2019.

That’s caused wholesale spot prices for pork to skyrocket. They jumped 40% in October alone and have more than doubled since the first African swine fever cases were reported in China in August 2018.

China’s Growing Pork Deficit

Domestic pork production doesn’t fulfill the consumption demand

Demand fulfilled by Chinese

production

(1 million metric tons)

Demand fulfilled by world supply

Estimated pork supply deficit

2018

2019

2020

Demand fulfilled by

Chinese production

(1 million metric tons)

Demand fulfilled

by world supply

Estimated pork

supply deficit

2018

2019

2020

Even if all the world’s supply

will be exported to China, it can only cover 10 million metric tons of the 22 million metric ton

pork supply deficit.

Demand fulfilled by Chinese production

(1 million metric tons)

Demand fulfilled by

world supply

Estimated pork supply

deficit

2018

2019

2020

Even if all the world’s supply

will be exported to China, it can only cover 10 million metric tons of the 22 million metric ton

pork supply deficit.

Source: USDA
Note: Based on five-year average consumption

Such a massive plunge in domestic pork production can’t immediately be filled by any country or any alternate source of animal protein.

Spain’s experience with the disease suggests that a cull alone won’t be enough to solve the problem. The country implemented strict sanitary measures and industrialized its hog production system but it took 35 years and help from the European Union before the disease was eradicated in 1995. The Italian island of Sardinia has been trying unsuccessfully to get rid of the virus for four decades, and its hog population is a fraction of China’s.

Mystery Source
One of the reasons why African swine fever is so hard to eradicate is that it’s easy to transmit. Despite prevention and control measures, African swine fever has continued to widen its hold in Europe, reaching Belgium, Bulgaria, Czech Republic, Hungary, Moldova, Romania, Serbia, and Slovakia since 2014.

Multiple Routes

Main sources of African swine fever into Europe

Raw pork waste at airport or port

Georgia

2007

Sardinia

1978

Lisbon

1957

Malta

1978

Movement of pork or pig product

Belgium

1985

Italy

1983

Portugal

1960

Spain

1960

Natural ranging of infected wild boar

Russia

2007

Estonia

2014

Lithuania

2014

Belgium

2018

Poland

2014

Infected ticks

Portugal

1999

Raw pork waste at airport or port

Movement of pork or pig product

Belgium

1985

Georgia

2007

Sardinia

1978

Italy

1983

Portugal

1960

Lisbon

1957

Malta

1978

Spain

1960

Infected ticks

Natural ranging of infected wild boar

Russia

2007

Estonia

2014

Portugal

1999

Lithuania

2014

Belgium

2018

Poland

2014

Raw pork waste at airport or port

Movement of pork or pig product

Belgium

1985

Georgia

2007

Sardinia

1978

Italy

1983

Portugal

1960

Lisbon

1957

Spain

1960

Malta

1978

Infected ticks

Natural ranging of infected wild boar

Russia

2007

Estonia

2014

Portugal

1999

Lithuania

2014

Belgium

2018

Poland

2014

Raw pork waste at airport or port

Movement of pork or pig product

Natural ranging of infected wild boar

Infected ticks

Belgium

1985

Georgia

2007

Russia

2007

Estonia

2014

Sardinia

1978

Italy

1983

Portugal

1999

Portugal

1960

Lisbon

1957

Lithuania

2014

Malta

1978

Spain

1960

Belgium

2018

Poland

2014

Source: J.M. Sánchez-Vizcaíno, et al, 2014, World Organization for Animal Health (OIE)

In addition to direct contact with an infected pig, the virus can be passed on to animals that eat virus-laden pork or feed, via contaminated clothing or equipment or when a pig drinks water containing even minute quantities of the virus.

Studies show that the strain in China closely resembles one that’s been spreading in Russia and other parts of Europe for more than a decade. But scientists still don’t know the route it took to get into the world’s most populous nation. Without knowing how the virus got in, China’s customs officials will have a harder time preventing repeated introductions.

The disease is now in Cambodia, Laos, Mongolia, Myanmar, North Korea, South Korea, Philippines, Timor Leste, Vietnam and possibly other neighboring countries that lack the resources to identify and control the disease. That increases the risk that, even if China does manage to control the disease domestically, it could re-enter the country via people or pork products that cross the border.

Transcontinental Contagion

How African swine fever spread from Africa to Europe to Asia from 2005 to 2019

Click to replay 👆

Source: World Organization for Animal Health (OIE), as of October 29, 2019

Dirty Garbage
Scientists say the virus may have arrived in China the same way it entered Europe in early 2007. A United Nations report suggests some food-waste containing pork was dumped from a ship visiting the port of Poti on the Georgian Black Sea and then eaten by one of the local pigs that are allowed to scavenge on garbage. Within weeks, 30,000 pigs had died and 80 percent of Georgia’s districts were thought to be infected.

Pigs and their feral wild-boar cousins are quintessential waste disposal units, guzzling on protein from a wide variety of sources, including kitchen scraps, manure and dead hogs. While the omnivorous nature of the animals makes them low-cost nutrient converters, it’s also a key reason why African swine fever spreads easily.

A review of outbreaks showed that almost half were caused by the spread of virus material on vehicles and on non-disinfected workers, with feeding pigs contaminated swill or food scraps the second-biggest source. Feeding raw swill to pigs has been outlawed in China because of the risk of disease transmission, but clandestine use of non-heat-treated restaurant and household waste is reported to persist among suburban and smallholder farmers. About half of China’s producers raise fewer than 500 hogs each.

Sticky Germs

Epidemiological studies of 68 outbreaks in China revealed three major causes of spread

19%

Transportation of live

pigs and their products

34%

Feeding pigs swill

68

outbreaks

46%

Virus carried on

vehicles and workers

without disinfection

68

outbreaks

46%

34%

19%

Feeding pigs swill

Virus carried on

vehicles and workers

without disinfection

Transportation

of live pigs and

their products

68

outbreaks

46%

34%

19%

Virus carried on

vehicles and workers

without disinfection

Feeding pigs swill

Transportation

of live pigs and

their products

Source: China’s Ministry of Agriculture and Rural Affairs

So far, government efforts to halt the spread through quarantining and sanitizing infected farms, culling vulnerable pigs, closing markets and restricting the movement of hogs have been insufficient, and the disease has become entrenched across the country.

Surreptitious
The virus is also hard to track. Pigs may incubate it for five to 15 days and can shed infectious particles for one to two days before falling ill. That means the virus can be silently spread in the waste, meat and blood of infected pigs that don’t appear to be sick, especially when they are illegally transported or slaughtered before diagnosis.

In China, pigs are routinely trucked hundreds of miles as farmers and traders seek to take advantage of regional differences in livestock and meat availability and prices, as well as a preference for fresh meat. When hogs arrive at a new farm, they are typically mixed immediately with other swine, facilitating transmission of the disease.

Hiding Outbreaks
Identifying outbreaks early is critical for mitigating their spread. The Chinese government has pledged to pay a subsidy of 1,200 yuan per pig to compensate farms for losses, but some local governments are reported to be withholding payments—removing an incentive for farmers to report the disease.

In some instances, individuals have even been punished for publicizing outbreaks. A hog manager in Shandong province was allegedly arrested for reporting infected pigs to the national government after his efforts to alert local officials were ignored.

A pork stall at a market in Hanoi, Vietnam
An empty meat stall in Hong Kong. Photographer: Paul Yeung/Bloomberg

Saturated Blood
The virus, though, doesn’t need traveling swine to spread. A single drop from an acutely infected pig can contain 50 million virus particles, and just one of those particles ingested in contaminated drinking water may be enough to transfer the disease to another pig.

Infected blood, or fluids from urine, saliva or feces, can be carried in dirt on truck tires and shoes, allowing the disease to travel hundreds of miles quite rapidly. Contaminated sources require heating to 60 degrees Celsius (140 Fahrenheit) for 30 minutes to be rendered safe.

Tens of thousands of swine have been infected in China and their carcasses represent an enormous environmental risk, requiring careful handling and disposal. In Romania, the contamination of the Danube River from dead hogs was implicated in the virus’s spread to a 140,000-pig farm.

Tough Survivor
The germ is hardy, capable of remaining active in water for a month, in meat and blood at room temperature for several months and for six years in cold, dark conditions. It’s resistant to temperature extremes, and can survive a day in vinegar-strength acids.

Stealthy Bug

African swine fever can survive temperature and pH extremes

Pork products

Others

Pork products

Others

15 minutes in unprocessed

meat heated to 70°C (158°F)

3.5 hours at 56°C

5 days in feces at 4-10°C

5 days in urine

22 hours at pH 3.1 (an acidity

similar to vinegar)

5 days in animal feed at room

temperature

5 days in cooked ham

11 days in feces at room

temperature

16 days in organs at room

temperature

25 days in slurry

30 days in pigs that

survive infection

30 days in pepperoni

and salami sausage

60 days in water at room

temperature

60 days in canned stew

100

104 days in frozen meat

or chilled meat

105 days in offal

112 days inIberian loins

140 days in Iberian hams

and white Serrano hams

182 days in salted meat

200

300 days in dried meat and skin

400

399 days in Parma hams

500

525 days in blood at 4-10°C

600

700

More than 2 years in frozen

pig organs

6 years at 5°C with no light

Pork products

Others

15 minutes in unprocessed meat

heated to 70°C (158°F)

3.5 hours at 56°C

5 days in feces at 4-10°C

22 hours at pH 3.1 (an acidity similar

to vinegar)

5 days in urine

5 days in animal feed at room temperature

5 days in cooked ham

11 days in feces at room temperature

16 days in organs at room temperature

25 days in slurry

30 days in pigs that survive infection

30 days in pepperoni and salami sausage

60 days in water at room temperature

60 days in canned stew

100

104 days in frozen meat or chilled meat

105 days in offal

112 days inIberian loins

140 days in Iberian hams and white

Serrano hams

182 days in salted meat

200

300 days in dried meat and skin

400

399 days in Parma hams

500

525 days in blood at 4-10°C

600

700

More than 2 years in frozen pig organs

6 years at 5°C with no light

Sources: World Organization for Animal Health (OIE), M.C. Niederwerder et al, S. Farez et al, K. Davies et al, Beltran-Alcrudo et al, European Food Safety Authority

There are no published studies reporting the incidence of African swine fever virus detected in food in China. But the virus has been in Chinese pork products that were confiscated by customs officials in Australia, Japan, Northern Ireland, Philippines, South Korea, Taiwan, and Thailand, suggesting that the virus has permeated the food chain in China.

Even if China is able to stop the virus transmitting from pig to pig, two other disease vectors may frustrate eradication efforts: wild boars and Ornithodoros ticks. These are the natural hosts of African swine fever virus and are widely distributed in China, though it’s not yet known what role they are playing in spreading the disease there. Zhejiang province, south of Shanghai, has about 150,000 wild boars.

While infected wild boars have been reported in China, the Russian Far East, and South Korea, scientists believe human activities are a bigger contributor to the spread of African swine fever.

A pork stall at a market in Hanoi, Vietnam
Disinfectant is sprayed onto the back of a truck near a pig farm in Yeoncheon, South Korea. Photographer: SeongJoon Cho/Bloomberg

No Vaccine
Despite 50 years of research, scientists haven’t managed to develop a vaccine that’s safe and effective against African swine fever, and even if recent research proves fruitful, it could be years before an effective shot becomes commercially available.

One of the earliest attempts—based on a live, weakened form of the virus—was abandoned after it was found the vaccine gave pigs a debilitating and disfiguring disease.

Studies have found that the animals which recover from an initial African swine fever infection are resistant to some other strains, but scientists aren’t sure what exactly confers that protection or how best to evaluate the potential efficacy of candidate vaccines.

One of their difficulties is that the large, complex DNA virus that causes African swine fever has some 170 genes and 80 proteins, many of them specialized in evading different aspects of the pig immune system.

More recent attempts to produce an immunization using viruses that lack key disease-causing genes appear to be safe. Still, researchers are yet to carry out large field trials to demonstrate effectiveness in commercial farms—a necessary step for gaining regulatory approval. That’s not stopping some farmers from using unauthorized, experimental vaccines, potentially undermining efforts to both develop effective immunizations and control the disease.

With a tough virus to eradicate and no vaccine available anytime soon, the best way China can protect its domestic pork industry from African swine fever is to carefully monitor and control the germs on every pig, person and product entering and leaving hog farms. That would mean turning China’s 26 million piggeries into veritable biocontainment facilities.