African Swine Fever in Pigs: Symptoms, Spread, and Prevention
- See your vet immediately if your pig has a high fever, weakness, red or blotchy skin, vomiting, diarrhea, breathing trouble, abortion, or sudden collapse.
- African swine fever (ASF) is a highly contagious viral disease of domestic and feral pigs. It does not infect people, but people, clothing, equipment, pork products, and vehicles can help spread it.
- There is no approved treatment that cures ASF. Rapid reporting, testing, isolation, and strict biosecurity are the main response steps.
- ASF has never been found in the United States as of March 15, 2026, but USDA considers it a serious foreign animal disease threat.
- Early veterinary evaluation matters because ASF can look like other severe pig diseases, including classical swine fever, septicemia, and erysipelas.
What Is African Swine Fever in Pigs?
African swine fever, or ASF, is a serious viral disease of pigs that affects both domestic pigs and feral swine. It can cause very high death rates, especially with highly virulent strains. ASF does not infect people, and properly prepared pork is considered safe for human consumption, but the virus can move between pigs through contaminated meat, blood, equipment, clothing, and other materials.
This disease is especially concerning because it can spread quickly and may kill pigs before a pet parent notices many warning signs. In some pigs, the illness is sudden and severe. In others, signs may be less specific at first, such as fever, low appetite, and weakness. That overlap with other pig diseases is one reason your vet and animal health officials take suspected cases so seriously.
As of March 15, 2026, ASF has not been detected in the United States, but it remains present in multiple regions of the world, including parts of Europe, Asia, the Caribbean, and Africa. For pet pigs, backyard pigs, and small farms, prevention and fast reporting are the most important tools.
Symptoms of African Swine Fever in Pigs
- High fever
- Weakness, lethargy, or reluctance to stand
- Decreased appetite
- Red, blotchy, bruised, or darkened skin
- Vomiting or diarrhea
- Coughing or difficulty breathing
- Abortions in pregnant pigs
- Sudden death
See your vet immediately if your pig has fever, weakness, red or blotchy skin, vomiting, diarrhea, breathing trouble, abortion, or sudden collapse. These signs are not specific to ASF, but they can point to a medical emergency or a reportable foreign animal disease.
Do not move the pig to another property, sale, show, or gathering while you are waiting for guidance. Limit contact with other pigs, people, boots, tools, and vehicles until your vet advises you on the next step.
What Causes African Swine Fever in Pigs?
ASF is caused by the African swine fever virus, a hardy virus that can survive in blood, tissues, and some pork products for long periods. Pigs can become infected through direct contact with sick pigs or carcasses, or indirectly through contaminated feed, bedding, trailers, clothing, boots, needles, tools, and housing areas.
One major concern is swill or garbage feeding. Feeding pigs food waste that contains contaminated pork products can spread the virus. In the United States, the Swine Health Protection Act regulates feeding human food waste to pigs because this practice can spread serious diseases, including ASF.
Feral swine also matter. Outdoor pigs may be exposed if fencing is poor or if wild pigs can reach feed, water, or shared ground. In some parts of the world, certain soft ticks can also help maintain and spread the virus, although this is not the main route most U.S. pet parents think about day to day.
People do not get sick from ASF, but they can carry the virus on hands, shoes, clothing, equipment, and vehicles. Travel to affected countries, contact with pigs overseas, and bringing pork products home from affected regions all increase risk.
How Is African Swine Fever in Pigs Diagnosed?
ASF cannot be diagnosed by symptoms alone. Your vet will start with a history, physical exam, temperature check, and questions about recent travel, visitors, new pigs, pork exposure, outdoor access, and contact with feral swine. Because ASF can resemble classical swine fever, erysipelas, salmonellosis, septicemia, and other severe illnesses, lab testing is essential.
If ASF is suspected, your vet may coordinate with state or federal animal health officials. Testing usually involves PCR or other laboratory methods on blood or tissues. Merck notes that samples such as blood, spleen, kidney, lymph nodes, and tonsils may be used for confirmation, depending on the situation and whether a pig has died.
This is a reportable foreign animal disease concern, so the response is different from a routine sick visit. Your vet may advise immediate isolation, movement restrictions, and strict cleaning steps while official guidance is pending. Fast reporting protects your pig, nearby pigs, and the wider swine community.
Treatment Options for African Swine Fever in Pigs
Spectrum of Care means you have options. Here are treatment tiers at different price points.
Budget-Conscious Care
- Urgent call to your vet or state animal health contact
- Immediate isolation of the pig from other pigs
- Basic exam and temperature check
- Movement stop for pigs, people, tools, and vehicles until guidance is given
- Initial sample collection or referral for official testing
Recommended Standard Treatment
- Urgent veterinary exam and foreign animal disease workup
- Official reporting and coordination with state or federal animal health authorities
- Diagnostic sampling such as blood and, when indicated, postmortem tissues
- Biosecurity plan for people, clothing, equipment, feed, and traffic flow
- Guidance on quarantine, cleaning, disinfection, and exposure tracing
Advanced / Critical Care
- Emergency herd investigation and regulatory response
- Expanded laboratory testing and necropsy coordination when needed
- Intensive biosecurity upgrades such as dedicated clothing, disinfection stations, and controlled entry points
- Exposure mapping for other pigs, visitors, vehicles, and feed sources
- Facility downtime, carcass handling, and official outbreak-control measures if disease is confirmed
Cost estimates as of 2026-03. Actual costs vary by location, clinic, and individual case.
Questions to Ask Your Vet About African Swine Fever in Pigs
Bring these questions to your vet appointment to get the most out of your visit.
- Do my pig's signs fit ASF, or are other emergencies more likely?
- Should I isolate this pig from my other pigs right now, and what does proper isolation look like at home or on the farm?
- Does this need to be reported to state or federal animal health officials today?
- What samples are needed, and where will they be tested?
- What should I do with boots, clothing, feeders, waterers, and tools that may be contaminated?
- Could recent travel, visitors, pork products, or outdoor exposure have increased my pig's risk?
- How do I protect my other pigs while we wait for results?
- What biosecurity changes would make the biggest difference for my setup going forward?
How to Prevent African Swine Fever in Pigs
Prevention starts with strong daily biosecurity. Keep new pigs separated before introducing them, limit visitors, clean and disinfect boots and tools, and avoid sharing equipment between properties unless it has been thoroughly sanitized. If your pig lives outdoors, work with your vet on fencing and management steps that reduce contact with feral swine.
Do not feed table scraps, food waste, or pork products to pigs unless your vet and local regulations clearly allow a safe, legal process. USDA specifically warns that garbage feeding can spread ASF. Store feed securely, keep rodents and wildlife away from feed areas, and clean up spilled feed that could attract wild animals.
Travel also matters. If you visit countries where ASF is present, avoid pig farms and pig contact. Do not bring pork products home from affected regions. If you were around pigs overseas, clean or discard footwear and clothing and avoid contact with pigs in the United States for the period recommended by USDA guidance.
Finally, know your pig's normal behavior. A pig that suddenly develops fever, weakness, red skin changes, vomiting, diarrhea, breathing trouble, abortion, or sudden death needs urgent veterinary attention. Fast action does not confirm ASF, but it gives your vet the best chance to protect your pig and prevent spread if a reportable disease is involved.