The History of ASF

African Swine Fever (AFS) has devastated herds in more than its country of origin. Pigs as far afield as Russian and China have been impacted over the years as have many areas of Europe.

The outbreak of ASF which began in China in 2018 continues to ravage herds across Asia and further afield. Sadly, the presence of this untreatable disease is nothing new. Countries around the world are on high alert due to the latest outbreaks.

The disease is endemic to sub-Saharan Africa, Madagascar, and Sardinia, meaning it does not occur naturally in any other location. This hasn’t helped with containing it. There have been many instances throughout history where it crossed over into other countries.

ASF outbreaks around the world

The first actively recognized outbreak occurred in Kenya in 1921, but this led to a retroactively-recognized incident having taken place in 1907. ASF was then officially present and contained in Africa for half a century until it broke the border of Portugal in 1957. Pigs near the capital city of Lisbon were fed with waste products from a plane which infected them with ASF. A second Portuguese outbreak followed in 1960.

Pigs being fed contaminated material was the cause of multiple ASF reports in the 20th century in Spain (1960), Italy (1983), and Belgium (1985). The Iberian Peninsula (Portugal and Spain) suffered continued outbreaks until the mid 1990s. Both countries eventually managed to eradicate the disease through a slaughter policy.

The first actively recognized outbreak occurred in Kenya in 1921, but this led to a retroactively-recognized incident having taken place in 1907.

France would suffer three reported outbreaks in 1964, 1967, and 1977 and is currently endangered by a recent ASF report from the Gaume region of southern Belgium. Cuba was hit by ASF in 1971 which resulted in the slaughter of, by some estimates, half a million pigs in an attempt to contain it. The disease was traced to a tick vector but was successfully eradicated. It was also successfully contained by the Dominican Republic, Brazil, and Haiti in the same year.

Belgium reported its first case in 1985 followed by The Netherlands in 1986. Georgia in the Caucasus was infected in 2007 and ASF spread out from there to five further regions – Russia, Azerbaijan, Belarus, Armenia, and Iran – via the illegal distribution of contaminated meat. The Czech Republic recently ended a two-year battle against the disease when it was announced they had finally eradicated it.

China is still fighting to get back on its feet since ASF struck last August.

How it’s spread

After last year’s outbreak in China, it’s more important than ever to know how to prevent the spread of African Swine Fever

If there’s any upside at all to African Swine Fever (ASF), it’s that it can’t infect humans. It’s a very different story for the huge number of pigs it has killed since it was first recorded in the early 1900s and the many more who are being culled today to fight the latest outbreak.

“Human immunity doesn’t represent the end of the road for an ASF germ. Far from it; humans can transmit the disease and are believed by some experts to be the way AFS will finally reach the U.S. There are many transmission routes…”

Human immunity doesn’t represent the end of the road for an ASF germ. Far from it; humans can transmit the disease and are believed by some experts to be the way AFS will finally reach the U.S. There are many transmission routes, also known as vectors, that ASF can exploit to travel on person to person and from place to place.

Physical contact/body fluids

Pig-to-pig and human-to-pig interaction contributes to the rapid spread of ASF. Blood, saliva, urine, and feces all harbor the disease. Since at least the last three on that list can easily be present at any time, they can quickly infect a whole herd through physical contact. Caregivers and vets are often exposed to such fluids in their daily work and can easily become carriers.

Herd-wide infection via this method can occur anywhere between one to nine days after first exposure. Even if infected animals are quickly partitioned, AFS may still find its way to the rest of the herd within 15 days. Research is ongoing into pigs who may be asymptomatic carriers making them difficult to spot.

Infected feed

ASF can be highly resistant to environmental temperatures, meaning that even infected feed stored at negative temperatures can contain the strain for months. A frozen carcass may even harbor ASF for several years.

Swill feeding is common around the world and has been identified as a major factor in ASF transmission. Seeds and grass in pig feed have also been linked to infection since these items may have been infected by wild boar prior to consumption by the pigs. The U.S. Department of Agriculture (USDA) offers further in-depth information on this aspect of ASF risk.

A recent study by Kansas State University highlights the risk of infected feed by showing how virulent ASF can be. It only needs to be present in feed at a low level to make repeated consumption from an infected source a danger to herds. When we consider that millions of kilos of feed products are entering the U.S. from countries where ASF is spreading, it makes vigilance on the feed front crucial.

Contact with a secondary medium

A secondary medium could be clothing, transportation, or equipment. Caregivers and producers may be taking the utmost care in screening their herds and enforcing biosecurity in their own production chain, but all it takes is one unwitting visitor who has been in contact with ASF to carry the germ on the sole of a shoe, a medical tool, or a vehicle.

Ignorance as to how the disease spreads contributes to its threat.

It’s essential that caregivers and producers are aware of which countries are currently dealing with ASF outbreaks. It’s then easier to vet visitors by asking if they’ve been to any of these locations before coming to you. Be on guard if you or anyone you know/will be working with have broken any of the USDA’s safe tourism rules.

The recent outbreaks in Belgium have been driven by the hunting of wild boar infected by ASF. While the hunters may simply kill the animals and leave, their clothing may pick up the disease and transport it from the site since they were indirectly exposed to feral swine.

Tick vectors

Some tick species can be responsible for spreading ASF by drawing blood from an infected animal and then moving on to others. Tick saliva often contains a secretion with anesthetic properties. This saliva can also act as a transmission route from an infected tick.

This method of organism to organism infection is typically called a vector. The genus Ornithodoros are the main source of infection, with Ornithodoros moubata and Ornithodoros sonrai contributing as vectors to a lesser degree. ASF infection via tick typically takes less than five days. ASF can be found in tick vectors via three forms:

  • Transstadial. If a tick is infected at an early stage of life, it will carry the disease on through any future life stages (such as from larvae to nymph to fully grown)

  • Transovarial. An adult tick carrying ASF can pass it along to its many offspring; usually several thousand eggs

  • Sexual. Infected ticks pass the disease to mates during breeding

Low biosecurity/low awareness

Ignorance as to how the disease spreads contributes to its threat. ASF has yet to occur in the U.S., and that’s because we’re informed and aware of just how serious a threat ASF is. However, it’s going to be a real battle to keep our infection record clean in the year to come.

The risks of infection through multiple methods are higher than ever, and some experts believe it’s only a matter of time until the disease hits U.S. herds. Stay informed by following us at the links below and monitoring the World Animal Health Information Service.

Stay in control of your operation from anywhere.

EveryPig’s cutting edge herd monitoring technology is an indispensable tool for today’s pork owners, producers, and veterinarians. Its many features optimize awareness and empower caregivers to monitor, examine, and diagnose their herds from anywhere in the world in real-time.

The Potential Impact on North America

Nations around the world have been hit hard by African Swine Fever (AFS). There’s never been an outbreak in American history, but the growing threat is real. What price could U.S. pork producers pay if AFS makes its way across our borders?

African Swine Fever (AFS) is a virulent and resistant disease which can have a 100 percent mortality rate. It spreads in several ways; through physical contact, body fluids, contact with a secondary medium such as transportation, equipment or clothing, and via some tick species.

AFS has epidemic potential as a Transboundary Animal Disease. As the name suggests, AFS can quickly take hold in one country before doing so in another.

African Swine Fever (AFS) is a virulent and resistant disease which can have a 100 percent mortality rate.

China accounts for almost half of the world’s pork production, but the country has been rocked by the huge number of pigs lost to AFS. This has sent shockwaves through the industry and is expected to raise pork prices worldwide. Prices in China are expected to increase by as much as 78 percent by next year.

The following locations are in containment mode:

  • Asia – Republic of Korea, Viet Nam, and Myanmar 

  • Europe – Bulgaria, Belgium, Hungary, and Romania

Despite their efforts, Belgium reported a case outside of their containment zone which puts France at increased risk of AFS, while Australia has already reported its presence. These are distant snapshots of what could happen to America if AFS makes it here.

How America would feel the impact of AFS

As a world leader in the industry, China has an extensive pork production infrastructure. This doesn’t change the fact that it could take them between five and seven years to get back on their feet. America is a smaller nation, so we might have a recovery advantage as far as time goes. But, we’d still be looking at years to bounce back and face a virus strain with no approved vaccine or treatment.

The head of the world’s foremost food and agricultural bank revealed in a recent interview that many in the U.S. pork industry are not only downplaying the potential impact but can barely imagine it. Her opinion is that ASF is likely to arrive in America via a tourist or infected feed.

How significant is the tourist threat? A study conducted by the Center for Animal Health and Food Safety, College of Veterinary Medicine, University of Minnesota (OIE collaborating center on capacity building) and the Universidad Complutense de Madrid, Spain (OIE reference laboratory for ASF) turned up some alarming figures.

The risk of ASF being introduced by a tourist has increased by 183 percent.

The risk of ASF being introduced by a tourist has increased by 183 percent. The study highlighted five major airports which represent more than 90 percent of the potential risk: Newark (New Jersey), George Bush (Houston), Los Angeles (California), John F. Kennedy (New York), and San Jose (California). It was at Newark that the million pounds of infected pork (the largest such bust in U.S. history) was seized.

How America is guarding against this epidemic

The U.S. Department of Agriculture has always placed strict blocks on pork imports from any location hit by ASF. Now, they’re also coordinating their efforts with Canada and Mexico to make every possible avenue of entry into America even more secure. Canadian producers fear an AFS outbreak would cost them billions of dollars. Since America is an even larger player it would cost us far more.

It’s disturbing and relieving that our border security managed to seize a million pounds of pork infected with ASF that attempted to cross our borders in March.

It’s disturbing and relieving that our border security managed to seize a million pounds of pork infected with ASF that attempted to cross our borders in March. It was allegedly smuggled from China, and Director of Customs and Border Protections, Troy Miller, believes they saved American pork producers from $10 billion worth of damage

This proves nothing beats constant vigilance in preventing ASF from decimating American herds. Through the EveryPig app, there are steps U.S. caregivers can take to greatly increase their ability to monitor every aspect of their herd’s health.


Use the EveryPig app to protect your operation against African Swine Fever

EveryPig’s cutting edge herd monitoring technology is an indispensable tool for today’s pork owners, producers, and veterinarians. Its many features optimize awareness and empower caregivers to monitor, examine, and diagnose their herds from anywhere in the world in real-time. Daily check-ins allow staff to report on multiple essential metrics and notify vets of any medical issues which may need attention.

EveryPig uses Artificial Intelligence and machine learning to improve vigilance and increase the odds of preventing a health crisis before it occurs. Team members in the field can use visuals like photos and video alongside audio and statistical information to share data as and when it occurs.

Click here to learn how EveryPig can help you guard against African Swine Fever (ASF).

For more information, visit the African Swine Fever Organization and follow the Twitter feed