Vesicular Stomatitis in Pigs: Oral Lesions, Hoof Blisters, and Differential Diagnosis
- See your vet immediately if your pig has blisters, ulcers, drooling, or sudden lameness. Vesicular stomatitis can look like other serious reportable diseases, including foot-and-mouth disease.
- Common signs include fever, lip or tongue vesicles, excessive saliva, reluctance to eat, and painful lesions at the coronary band or between the claws that can cause limping.
- There is no specific antiviral treatment. Care is usually supportive while your vet and animal health officials confirm the cause and help prevent spread.
- Diagnosis depends on laboratory testing of lesion swabs, blister fluid, tissue, and sometimes blood. Clinical signs alone are not enough to tell vesicular stomatitis apart from other vesicular diseases.
- Typical initial veterinary and regulatory workup cost range in the U.S. is about $250-$900 for an exam, farm call, sample collection, and basic supportive care, but herd-level investigation, quarantine impacts, and repeat visits can raise total costs.
What Is Vesicular Stomatitis in Pigs?
Vesicular stomatitis is a viral disease that can occasionally affect pigs and cause blister-like lesions on the mouth, snout, and feet. In pigs, these lesions may show up on the lips, tongue, coronary bands, or between the claws. When the blisters rupture, they leave painful raw areas that can make eating and walking hard.
This condition matters because it can look almost identical to other vesicular diseases of swine, especially foot-and-mouth disease (FMD), as well as swine vesicular disease, vesicular exanthema of swine, and Senecavirus A infection. That means even a mild-looking case needs prompt veterinary attention and laboratory confirmation.
For many pigs, the illness is self-limiting and supportive care is the main treatment. Still, the bigger concern is not only the pig's comfort. It is the need to quickly identify the cause, limit spread, and follow reporting rules if your vet suspects a reportable vesicular disease.
Symptoms of Vesicular Stomatitis in Pigs
- Blisters or erosions on the lips, snout, gums, or tongue
- Excessive drooling or ropey saliva
- Reluctance to eat, chew, or drink because of mouth pain
- Lameness or reluctance to stand and walk
- Blisters, redness, or raw lesions at the coronary band or between the claws
- Fever early in the course of disease
- Mouth rubbing, lip smacking, or signs of oral discomfort
- Reduced activity or mild weight loss if eating is painful for several days
See your vet immediately if you notice any vesicles, blisters, or sudden raw ulcers on your pig's mouth or feet. These signs are important even if your pig still seems bright. Vesicular diseases can look alike at first, and some have major herd-health and regulatory consequences.
Urgency goes up if your pig is not eating, is dehydrated, cannot walk comfortably, or if more than one pig has similar lesions. Keep affected pigs separated as directed by your vet, avoid moving animals on or off the property, and limit shared equipment until the cause is clarified.
What Causes Vesicular Stomatitis in Pigs?
Vesicular stomatitis is caused by vesicular stomatitis virus (VSV), a virus in the genus Vesiculovirus. In the United States, the disease is seen mainly in horses and cattle, but pigs can be infected too. Transmission is not fully understood, though biting insects appear to play a major role. Black flies, sand flies, and biting midges have all been linked to spread.
Once the virus is on a farm or premises, it may also move through direct contact with saliva or fluid from ruptured vesicles. Contaminated equipment, feed containers, waterers, boots, trailers, and handling tools may help spread infectious material between animals or pens.
Outbreak risk tends to rise during seasons and in places where insect exposure is greater, especially near moving water. Not every pig with mouth or hoof blisters has vesicular stomatitis, though. Other diseases, including FMD, Senecavirus A infection, swine vesicular disease, and vesicular exanthema of swine, can cause very similar lesions, which is why your vet will focus on testing rather than appearance alone.
How Is Vesicular Stomatitis in Pigs Diagnosed?
Diagnosis starts with a careful exam and a strong index of suspicion. Your vet will look at the location of lesions, whether there is fever or lameness, how many pigs are affected, and whether there has been recent animal movement or insect exposure. Even so, clinical signs alone cannot reliably separate vesicular stomatitis from FMD or other vesicular diseases.
Because of that, suspected cases are handled as a reportable animal health event. Your vet may contact state or federal animal health officials right away. Samples can include lesion swabs, blister fluid, vesicular epithelium, and blood. Approved laboratories use tests such as RT-PCR, virus detection, and serology to identify the cause.
Differential diagnosis is a major part of the process. In pigs, your vet and regulatory officials may need to rule out foot-and-mouth disease, Senecavirus A, swine vesicular disease, and vesicular exanthema of swine. That is why pet parents should avoid moving pigs, sharing equipment, or trying home treatment first when fresh vesicles are present.
Treatment Options for Vesicular Stomatitis in Pigs
Spectrum of Care means you have options. Here are treatment tiers at different price points.
Budget-Conscious Care
- Prompt exam or farm call with isolation guidance
- Supportive care plan while awaiting testing direction
- Softened or moistened feed to reduce mouth pain with eating
- Basic hydration support and monitoring for dehydration
- Gentle lesion hygiene as directed by your vet
- Strict movement pause and basic biosecurity steps
Recommended Standard Treatment
- Veterinary exam plus sample collection for approved diagnostic testing
- Pain-control and supportive-care recommendations tailored by your vet
- Fluids or more active hydration support if intake is reduced
- Monitoring for secondary bacterial infection and foot pain
- Isolation of affected pigs and cleaning/disinfection plan
- Insect-control measures around housing and handling areas
Advanced / Critical Care
- Repeat veterinary visits or referral-level monitoring
- IV or intensive fluid support for pigs not drinking adequately
- More aggressive wound and foot-care support
- Management of severe lameness, recumbency, or marked oral pain
- Expanded herd assessment and repeated diagnostics as directed
- Enhanced quarantine, vector control, and biosecurity oversight
Cost estimates as of 2026-03. Actual costs vary by location, clinic, and individual case.
Questions to Ask Your Vet About Vesicular Stomatitis in Pigs
Bring these questions to your vet appointment to get the most out of your visit.
- Do these lesions look like a vesicular disease that needs immediate reporting?
- What diseases are on the differential list for my pig, including foot-and-mouth disease and Senecavirus A?
- What samples need to be collected, and how long might results take?
- How should I isolate this pig and handle feed bowls, waterers, boots, and equipment safely?
- What signs would mean my pig is becoming dehydrated or needs more intensive supportive care?
- What feeding changes can help if mouth lesions are making chewing painful?
- What insect-control steps make the most sense for my property right now?
- When is it safe to resume normal movement, introductions, or transport after a suspected case?
How to Prevent Vesicular Stomatitis in Pigs
Prevention focuses on biosecurity and insect control. Reduce exposure to biting insects where possible, especially during higher-risk seasons. Your vet may suggest manure management, drainage improvements, screens, fans, approved insecticides, and keeping pigs away from areas with heavy insect activity or moving surface water when local risk is elevated.
It also helps to limit disease spread through people and equipment. Clean and disinfect shared tools, feeders, trailers, and handling surfaces. Use dedicated boots and clothing for pig areas when possible, and avoid sharing equipment between groups without cleaning.
Do not move pigs with suspicious mouth or foot lesions. New or returning animals should be introduced carefully and monitored for signs of illness. If you notice fresh vesicles, drooling, or sudden lameness, contact your vet right away. Early reporting protects your pig, other animals on the property, and the broader swine community.