What Is Swine Fever and Can We Prevent its Resurgence?

Keep your hogs safe from this lethal disease by following these key preventative tips.

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by Adobestock/Aleksey Sagitov

What is swine fever? While ASF is not transmittable to humans, it spreads easily and rapidly among swine, and humans can transport the disease. Learn how to recognize African swine fever symptoms to protect your and your neighbors’ animals, and how to practice good biosecurity.

African swine fever (ASF) is a viral disease that affects the hog family and is almost always fatal. ASF was discovered in Kenya in the early 20th century and is endemic to much of the African continent. In recent years, it’s spread across Asia and Eastern Europe. While it had been eradicated from the Americas for 40 years, it was recently found in Haiti and the Dominican Republic. How does it spread, and what does this mean for hog owners?

African Swine Fever Symptoms

ASF affects a pig’s vascular system and causes the infected animal to bleed out internally. African swine fever symptoms are often accompanied by a high fever. There are roughly 24 genotypes of ASF. Clinical forms are divided into peracute (severe), acute, subacute, chronic, and asymptomatic presentations.

Peracute presentations are associated with loss of appetite, little to no activity, and a high fever of 105.8 to 107.6 degrees Fahrenheit. Sudden death without any warning signs can also happen.

Acute presentations have an incubation period of 4 to 7 days and are associated with blotchy skin, bloody diarrhea, vomiting, eye and nose discharge, loss of appetite, general weakness, and a fever of 104 to 107.6 degrees. Death generally follows within 6 to 9 days or 11 to 15 days, depending on the strain.

Subacute presentations have less obvious symptoms, including hemorrhages, swollen joints, fevers of varying severity, edema, and pneumonia. Death frequently occurs within 7 to 20 days.

Chronic presentations are generally associated with areas where ASF is already established, and signs include swollen joints, pneumonia, and a mild fever.

What Is Swine Fever?

Young wild Boar being watched over by parent

It’s vital to reduce and eliminate the potential spread of ASF. While it hasn’t been found in the United States so far, anyone who works with or around pigs should be able to recognize African swine fever symptoms. These include high fever, decreased appetite, weakness, red blotchy skin, skin lesions, diarrhea, vomiting, coughing, and difficulty breathing. Report animals with these symptoms immediately to the U.S. Department of Agriculture (USDA) for testing. When handling a potentially infected animal, remember that anything coming out of the pig could be infected, especially its blood. Vomit, diarrhea, blood, and meat from an infected pig can quickly spread this deadly disease and should be handled with extreme caution.

While ASF is not transmittable to humans, it spreads easily and rapidly among swine, and humans can transport the disease. It can be transferred via your clothes or boots when you visit a farm or butcher shop, and it can survive for months in pork products made from an infected animal. When visiting countries in which ASF is currently found, don’t bring home any clothing or shoes that were worn while visiting a farm with pigs, a butcher shop or meat market, or an area with wild boars. Something as seemingly innocuous as bringing home sausage could potentially introduce ASF if the product wasn’t completely cured and your pigs ate even a small portion from the garbage.

With the recent avian influenza outbreak across the United States, we’ve witnessed how a disease like this can spread and impact our lives through loss of our own livestock or the prices at the grocery store increasing due to widespread culling. Preliminary estimates from experts suggest that if ASF was introduced and allowed to spread in the United States, it would cost between $15 billion and $50 billion to eradicate the disease, taking into account the duration of the outbreak, loss of livestock, testing, and the need to disinfect areas before they could be used for swine again.

Currently, the USDA is working with the Coast Guard to eliminate ASF’s potential spread to the United States. The Coast Guard monitors for people illegally transporting animals, and this monitoring is especially vigilant around Puerto Rico, because of its close proximity to the Dominican Republic, which does have an active ASF outbreak. Even though Puerto Rico hasn’t had any confirmed cases of ASF, all pork must be treated before being shipped from Puerto Rico to the mainland U.S. The Coast Guard is also tasked with ensuring trash from ships is handled properly to prevent contamination in that form.

African Swine Fever Prevention

Even if you’re not prone to visiting farms across the world, you should still be aware of ASF and its ramifications. It’s up to you to protect not only your own animals but also your neighbors’. Healthy animals are productive animals that often provide a source of either money or food.

Cute little pig on a farm in the straw

To help prevent the introduction and spread of ASF, practice good biosecurity. Don’t spread your farm’s germs to other farms, and vice versa. Designate shoes and clothes for doing farm chores, and don’t wear those clothes elsewhere. If you visit a farm, animal market, butcher shop, or anywhere else you may come into contact with animal excrement or bodily fluids, immediately change when you get home. Disinfect your shoes and wash the clothes you wore. Some strong disinfectants kill the virus, and a few are available to the general public, including hydrogen peroxide. (For a full list, visit the USDA Animal and Plant Health Inspection Service.) Most heavy-duty disinfectants, however, are restricted in their usage. Even though disinfecting is an option, prevention is the best solution.


What Is Swine Fever? Learn More!

To learn more about African swine fever and what’s being done to prevent its resurgence, visit these websites to get trusted sources of information on animal health and disease management:

USDA Animal and Plant Health Inspection Service

World Organisation for Animal Health

American Veterinary Medical Association

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