On May 28, a 3-year-old mare in Polk County, Wisconsin, tested positive for equine influenza, equine herpesvirus-1 (EHV-1), and equine herpesvirus-4 (EHV-4). The mare developed a fever and cough on May 25. She is currently quarantined.EDCC Health Watch is an Equine Network marketing program that utilizes information from the Equine Disease Communication Center (EDCC) to create and disseminate verified equine disease reports. TheEDCCis an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.EHV 101Herpesvirus is highly contagious among horses and can cause a variety of ailments in equids, including rhinopneumonitis (a respiratory disease usually found in young horses), abortion in broodmares, and EHM.In many horses, the first or only sign of EHV-1 infection is fever, which can go undetected.In addition to fever, other common signs of EHV-1 infection in young horses include cough, decreased appetite, depression, and a nasal discharge. Pregnant mares typically show no signs of infection before they abort, and abortions usually occur late in gestation (around eight months) but can be earlier. Abortions can occur anywhere from two weeks to several months following infection with EHV-1.Horses with EHM usually have a fever at the onset of the disease and might show signs of a respiratory infection. A few days later, neurologic signs such as ataxia (incoordination), weakness or paralysis of the fore- and hind limbs, urine retention and dribbling, loss of tail tone, and recumbency (inability to rise) develop.Herpesvirus is easily spread by nose-to-nose or close contact with an infectious horse; sharing contaminated equipment including bits, buckets, and towels; or clothing, hands, or equipment of people who have recently had contact with an infectious horse.Routine biosecurity measures, including hygiene and basic cleaning and disinfection practices, should be in place at all times to help prevent disease spread.Current EHV-1 vaccines might reduce viral shedding but are not protective against the neurologic form of the disease. Implementing routine biosecurity practices is the best way to minimize viral spread, and the best method of disease control is disease prevention.About Equine InfluenzaEquine influenzais a highly contagious respiratory disease that infects horses, ponies, and other equids, such as donkeys, mules, and zebras. The virus that causes it is spread via saliva and respiratory secretions from infected horses. Horses are commonly exposed via horse-to-horse contact; aerosol transmission from coughing and sneezing; and contact with humans contaminated hands, shoes, or clothes or contaminated tack, buckets, or other equipment.Clinical signs of equine influenza infection can include a high fever (up to 106F); a dry, hacking cough; depression; weakness; anorexia; serous (watery) nasal discharge; and slightly enlarged lymph nodes. Consider monitoring your horses health at shows by taking his temperature daily, which can help you pick up on signs of infection early and take appropriate measures to reduce disease spread.Vaccinationis an important and inexpensive way to protect your horse. US Equestrian requires proof that horses have had an equine influenza vaccination within the six months prior to attending organization-sanctioned competitions or events. Your veterinarian can help you determine what other vaccines your horse might benefit from.In addition to vaccinating, following strictbiosecurity protocolscan help reduce your horses chance of infection and disease. Such measures include quarantining new equine arrivals at barns, disinfecting buckets and equipment, and preventing nose-to-nose contact between horses.

On May 27, a 5-year-old Quarter Horse gelding in Kalamazoo County, Michigan, tested positive for strangles. The gelding developed clinical signs on May 15, including lethargy and intermittent fever. He is now recovering.EDCC Health Watch is an Equine Network marketing program that utilizes information from the Equine Disease Communication Center (EDCC) to create and disseminate verified equine disease reports. TheEDCCis an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.About StranglesStranglesin horses is an infection caused byStreptococcus equisubspeciesequiand spread through direct contact with other equids or contaminated surfaces. Horses that arent showing clinical signs can harbor and spread the bacteria, and recovered horses remain contagious for at least six weeks, with the potential to cause outbreaks long-term.Infected horses can exhibit a variety of clinical signs:FeverSwollen and/or abscessed lymph nodesNasal dischargeCoughing or wheezingMuscle swellingDifficulty swallowingVeterinarians diagnose horses using polymerase chain reaction (PCR) testing with either a nasal swab, wash, or an abscess sample, and they treat most cases based on clinical signs, implementing antibiotics for severe cases. Overuse of antibiotics can prevent an infected horse from developing immunity. Most horses make a full recovery in three to four weeks.A vaccine is available but not always effective. Biosecurity measures of quarantining new horses at a facility and maintaining high standards of hygiene and disinfecting surfaces can helplower the risk of outbreakorcontain one when it occurs.

Fly season can turn even the most laid-back horse into a fidgety, itchy, stressed version of themselves. If youve found yourself swatting midges in the yard, re-filling fly spray every five minutes, or watching your horse stamp and tail-swat all afternoon, youre not alone.The good news: you dont need a perfect setup to make a big difference. A few smart changes to turnout, stable routines, and protection can reduce bites, rubbing and stress and make summer far more comfortable for your horse.Why flies and midges are such a problem in the UKIn the UK, we tend to get a mix of warm spells, damp ground and still evenings ideal conditions for:Midges (Culicoides), often worst at dawn and duskHorseflies, more common on hot, bright daysStable flies and house flies, attracted to manure and damp beddingSome horses cope fine. Others react strongly, especially if theyre prone to sweet itch or have sensitive skin.Step 1: Start with turnout timing (its often the biggest win)If your horse is being tormented in the field, changing when theyre out can help as much as changing what they wear.Try:Avoiding dawn and dusk turnoutfor itchy horses (midge peak times)Bringing in before the evening drop in temperatureif midges are your main issueChoosing breezier fieldswhere possible midges struggle in windUsing a field shelteror shaded area so your horse can get out of direct sun (horseflies love bright, hot conditions)If you cant change turnout hours, dont worry focus on the protection steps below.Step 2: Make the stable less attractive to fliesFlies love warmth, moisture and organic material. Small changes can reduce how many hang around your horse.Practical stable tweaks:Muck out thoroughly(especially wet patches) and remove droppings from the yardKeep feed bins sealedand sweep up spillsImprove airflow: open top doors, use safe ventilation, and avoid damp cornersDry rugs and pads properlybefore re-using (damp fabric can irritate skin and attract flies)If you use a fan, make sure its positioned safely and doesnt blow dust directly at your horses face.Step 3: Choose the right fly rug (fit matters more than fancy features)A fly rug can be a game-changer but only if it fits well and suits your horses routine.What to look for in a fly rugGood coverage: belly flap, neck cover, and a generous tail flap if your horse needs itBreathable fabricthat wont overheat your horseSmooth lining at the shouldersto reduce rubbingSecure fasteningsthat dont twist when your horse rollsQuick fly rug fit checklistThe rug sitsevenly across the chestwithout pulling backNo tightness at the shoulders when your horse walks forwardThe neck section doesnt rub the mane or press into the witherBelly straps are secure but not restrictiveNo gaping around the legs where flies can get inIf your horse is rubbing more after youve added a fly rug, its often a fit issue or a sign they need extra skin support (see Step 5).Step 4: Use fly repellents strategically (not just more)Fly sprays and repellents work best when you treat them like part of a routine.Tips that help:Apply before turnout, not after your horse is already being bittenFocus on common target areas:belly line, chest, legs, neck, and around the ears(avoid eyes and nostrils)Re-apply more often after heavy sweat or rainPatch test new products on sensitive horsesFor face protection, many owners find a fly mask is more reliable than repeated spraying.Step 5: Support the skin (especially for itchy horses)If your horse is already rubbing, the skin barrier can become inflamed and reactive which makes the itch-scratch cycle harder to break.A calm, consistent routine helps:Gently wash off sweat and grime(dont over-wash; it can dry the skin)Dry thoroughly, especially under rugsUsesoothing, horse-safe skin productson irritated areasKeep mane and tail tidy to reduce tangles and rubbing damageSweet itch noteIf your horse gets seasonal itching every year (mane, tail, belly line), its worth treating it as a whole-season plan, not a one-off flare-up. Early protection is usually easier than catching up once theyre sore.Step 6: Dont forget the basics water, salt and stressHot weather and fly irritation can both increase stress. A horse thats uncomfortable may:Drink less (or sweat more)Lose conditionBecome harder to handleMake sure your horse always has:Plenty of clean water(in field and stable)Access to salt(lick or feed, depending on your routine)A calm environment and a predictable routineWhen to get professional helpCall your vet (or speak to a qualified professional) if you notice:Broken skin, heat, swelling or signs of infectionSudden, severe itching that doesnt improveHives, widespread hair loss, or skin weepingYour horse seems unwell, lethargic, or off their feedQuick checklist: your fly-season routineAdjust turnout to avoid peak midge times (if possible)Keep stable and yard clean and dryChoose a fly rug that fits properly and offers the right coverageAdd a fly mask for sensitive facesApply repellent before turnout and re-apply as neededSupport the skin with a gentle, consistent care routineKeep water and salt available at all timesWhat to keep in your tack room this summerTo make fly season easier day-to-day, it helps to have a small grab-and-go kit:Fly rug and/or sweet itch rug (as needed)Fly maskFly repellentGentle shampoo or wash for sweaty daysSkin-soothing product for rubsHoof pick (because summer fields still bring mud and thrush after rain)

On May 22, two horses at a boarding facility in Douglas County, Nebraska, tested positive for strangles. The horses developed clinical signs one week before being tested.Four additional horses are suspected to be positive, and 50 horses have been exposed.EDCC Health Watch is an Equine Network marketing program that utilizes information from the Equine Disease Communication Center (EDCC) to create and disseminate verified equine disease reports. TheEDCCis an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.About StranglesStranglesin horses is an infection caused byStreptococcus equisubspeciesequiand spread through direct contact with other equids or contaminated surfaces. Horses that arent showing clinical signs can harbor and spread the bacteria, and recovered horses remain contagious for at least six weeks, with the potential to cause outbreaks long-term.Infected horses can exhibit a variety of clinical signs:FeverSwollen and/or abscessed lymph nodesNasal dischargeCoughing or wheezingMuscle swellingDifficulty swallowingVeterinarians diagnose horses using polymerase chain reaction (PCR) testing with either a nasal swab, wash, or an abscess sample, and they treat most cases based on clinical signs, implementing antibiotics for severe cases. Overuse of antibiotics can prevent an infected horse from developing immunity. Most horses make a full recovery in three to four weeks.A vaccine is available but not always effective. Biosecurity measures of quarantining new horses at a facility and maintaining high standards of hygiene and disinfecting surfaces can helplower the risk of outbreakorcontain one when it occurs.

Diarrhea in horses can be challenging for veterinarians to diagnose and treat. | iStockChronic diarrhea in horses can be frustrating for owners and veterinarians alike, especially when the underlying cause isnt immediately clear. Amy Stewart, DVM, PhD, Dipl. ACVIM-LA, assistant teaching professor at the North Carolina State University College of Veterinary Medicine, in Raleigh, highlighted notable case studies and provided practical guidelines for managing this common condition at the 2026 Veterinary Meeting and Expo, held Jan. 17-21, in Orlando, Florida. Defining Diarrhea in HorsesOften defined as loose feces persisting for more than a week, chronic diarrhea in horses is usually linked to conditions of the large intestine (cecum, large colon, and small colon). Stewart pointed out that not everything that looks like diarrhea is pathologic (reflecting underlying disease). Fecal water syndrome, (FWS), in which horses excrete water along with normal-appearing bowel movements, has less serious health and welfare implications than true chronic diarrhea, she said.Systematic Approach to DiagnosisStewart explained that she generally starts with history and diet evaluation, fecal diagnostics, and noninvasive management approaches, which typically include dietary modification and specific GI supplements such as probiotics. She then progresses to more invasive procedures, such as duodenal and rectal biopsies, if needed. Endoscopy equipment is now widely available, making some of these diagnostics more accessible, she said.New Treatments for Diarrhea in HorsesVeterinarians consider fecal microbiota transplant (FMT) a promising, though not yet fully understood, intervention for severe or refractory chronic diarrhea cases, Stewart says. The emerging technique involves introducing healthy microbiota from a donors feces into the affected horse via nasogastric tube, but evidence in horses is limited and researchers are still working to determine optimal protocols.Beyond FMT, Stewart described sand management, careful evaluation of supplements, and close dietary monitoring as foundational for managing diarrhea. Steroids should be reserved for moderate to severe inflammatory cases, and all treatments must be carefully tailored to minimize risks, notably the debilitating hoof disease laminitis, she said.Notable Case StudiesStewart shared four of her own cases to illustrate the complexity of chronic diarrhea and offered treatment protocols:A young gelding with a history of chronic diarrhea was diagnosed with sand enteropathy (intestinal disease) via abdominal radiographs and a large colon impaction on rectal palpation. She treated him using sand-clearing agents (psyllium) and supportive enteral fluids, resulting in improvement. Stewart stressed that the amount of psyllium recommended to treat cases of significant sand accumulation is often much larger than what is found in some supplements.An older gelding developed severe diarrhea after a change in hay and administration of the (rarely used) drug, clioquinol (iodochlorhydroxyquin), which has broad-spectrum antibacterial effects on the fecal microbiome. He suffered life-threatening colitis (inflammation of the large or small colon)eventually traced to Salmonellaand needed intensive care, antibiotics due to extreme neutropenia (low white blood cell count), and an FMT to restore gut health.Another gelding dealt with what was presumed to be chronic FWS for more than two years. Diagnostics revealed mild inflammatory bowel disease, which responded best to dietary modificationremoving long-stem forage and reducing unnecessary supplements.The final case involved a horse with persistent diarrhea that turned out to be gastrointestinal lymphoma, confirmed by rectal mucosal biopsy. While prognoses for horses with this condition are typically guarded, treatment options include immunosuppressive steroids and, in select cases, chemotherapy to enhance comfort and quality of life.Take-Home MessageChronic diarrhea can have many causes. Dont jump to conclusions without a careful workup, Stewart said. As far as treatment, sometimes less is more. Simple diet modifications can be appropriate for nondistressed, otherwise-healthy horses with FWS. For true chronic diarrhea, newer therapies such as FMT offer hope for those managing particularly challenging cases.

Strategic equine deworming practices can help reduce the risk of parasite resistance. | Kristen Janicki/The HorseThe American Association of Equine Practitioners (AAEP) recommendations for deworming horses have changed substantially over the years, with the current emphasis on strategic targeting (treating certain horses) rather than the outdated rotation-based treatment of all horses at a facility.The primary objective of managing parasites in horses (as well as other equids) is to minimize parasite infections, ensuring the well-being of the animals and preventing the onset of clinical illness, says Jonathan Yardley, DVM, associate professor of clinical equine field services at The Ohio State Universitys College of Veterinary Medicine, in Columbus. Of the internal parasites found in adult (over 18 months of age) horses, the most damaging and potentially fatal for the horse are large strongyles (bloodworms), small strongyles (cyathostomes) and tapeworms. Other intestinal parasites include pinworms, threadworms, stomach worms and lung worms. In foals less than 1 year old, ascarids (roundworms) are the most problematic. Its worth noting that adult horses develop immunity to ascarids, making this less of a concern in older horses, says Yardley.The Life Cycle of Internal Parasites in HorsesThe life cycle of most equine internal parasites includes egg, larval, and adult stages. In general, the horse eliminates parasite eggs in the manure, depositing them onto the ground. The larvae develop in eggs and might hatch out, depending on the species, which allows the horse to ingest the parasites infective stage. The larvae then develop into adults within the gastrointestinal tract of the horse, with some parasite species migrating throughout the horses various organ systems as developing larvae before completing their life cycles.Previous Equine Deworming PracticesIn the past, owners dewormed their horses every four to eight weeks to treat them for any possible intestinal parasites, but more recent research shows this practice leads to parasite resistance. Scientists predicted resistance to horse dewormers (anthelmintics) a long time ago, says Antoinette Marsh, JD, MS, PhD, professor and service head at Ohio States Veterinary Medical Center Diagnostic Parasitology Lab. (Because) roundworms, small strongyles, and tapeworms reproduce quite rapidly and display high fecundity (the ability to produce a large number of offspring), the opportunity for genetic change significantly increases, she says. The presence of viable, reproducing worms remaining after any deworming gives surviving worms an advantage to reproduce as compared to nonresistant worms no longer around.The greater the deworming frequency, the faster resistance develops and, once this resistance occurs, it is not reversable, Marsh says. One parasite generation can pass drug resistance or susceptibility to the next, creating more resistant parasites over time if all the anthelmintic-susceptible parasites are killed off.Updated Equine Deworming PracticesCurrent deworming practices involve only treating the horses that need it the most (young horses and those with a heavy parasite burden) to slow the rate of parasite resistance development by maintaining a population of nonresistant parasites in the horses that are not receiving any deworming treatment.By leaving some drug-susceptible worms behind to mate or reproduce with drug-resistant worms, the drug-resistant genes in the worms can be diluted out when examining the parasite population as a whole, says Marsh. This nonresistant, untreated population is called refugia and is key to the success of current strategic deworming practices. The refugia will shed eggs containing the nonresistant genetic code into the environment and, over time, this will help dilute the drug-resistant parasite population.Because tapeworms are difficult to identify in fecal examinations, horses should be dewormed for tapeworms biannually or annually with a product containing praziquantel, says Marsh.Safe Deworming Practices for Adult HorsesIts important to note that the aim is not the complete elimination of all parasites within a specific individual, says Yardley. Pursuing total eradication is not only unattainable but also leads to the accelerated emergence of drug-resistant parasites.Because a heavy burden of internal parasites can cause weight loss, rough hair coats, poor performance, diarrhea, and colic in horses, the deworming plan should target maintaining the health of the horse and prevention of drug-resistant parasites. Fecal egg counts (FECs) are useful to determine the magnitude of egg shedding of an individual horse and the level of pasture contamination, says Marsh.After a FEC veterinarians categorize horses as nonshedders (no eggs seen), low shedders (usually less than 150 eggs per gram (EPG), moderate shedders (usually 150-500 EPG), or high shedders (usually more than 500 EPG). The FEC allows veterinarians to more clearly identify horses with consistently higher parasite egg counts. These horses are most likely to show signs of parasitism, such as weight loss, dull coat, or pot belly, and pass large numbers of infective eggs into the environment.Veterinarians select dewormers based on the FEC results, the horses age, and the type of parasite identified or suspected. Repeating the FEC 12-14 days after deworming provides information on the effectiveness of the dewormer used, says Marsh. The (repeat) test is referred to as a fecal egg count reduction test (FECRT). Essentially, do an FEC, deworm, repeat the FEC, and then use a formula to determine the treatment efficacy. When there is a 95% or greater reduction in parasite egg number in the feces, then that dewormer is still quite effective.Deworming FoalsWhile strategic targeting works well in adult horses, owners should take a different deworming approach for foals (under 1 year of age), says Yardley. Younger horses, due to their developing immune systems, should be treated as high shedders from birth to 2 years of age, he explains. Typically, high shedders require deworming every four months with a crucial assessment of their status through a fecal egg count. Foals aged zero through 6 months are especially vulnerable, having a higher population of roundworms in their intestines, he adds. Its noteworthy that these roundworms can migrate from the small intestine to the liver and then to the lungs of the foal, potentially leading to clinical signs resembling pneumonia. First deworming should be carried out at about 2-3 months of age, and a benzimidazole drug is recommended to ensure efficacy against ascarids. Second deworming is recommended just before weaning (approximately 4-6 months of age). Using ivermectin in young foals can be fatal if they have a heavy burden of adult roundworms in their small intestine, says Yardley, so it is important to have an FEC in a young foal before using ivermectin.Take-Home MessageMost horses do not need to be dewormed as frequently as researchers previously thought. The new equine deworming protocol allows veterinarians and horse owners to tailor the deworming program to each horse. Individualizing deworming strategies can minimize parasite contamination of the environment, improve the horses overall health, and limit parasite resistance.

University of KentuckyMartin-Gatton College of Agriculture, Food and Environmentresearchers have received awards from the U.S. Department of Agricultures National Institute of Food and Agriculture, totaling more than $1.8 million to address some of the most pressing health challenges facing horses and the equine industry.The projects, led byDepartment of Veterinary Sciencefaculty working across infectious disease, immunology, reproduction and musculoskeletal health, reflect UKs broad role in equine research and its connection to Kentuckys signature industry.The funded studies include work on non-antibiotic treatments for Rhodococcus equi pneumonia in foals, the genetic diversity of equine rotaviruses, the possible effect of joint corticosteroid injections on vaccine protection, the relationship between anti-inflammatory drug use and chronic musculoskeletal inflammation, and a long-sought biological signal tied to early pregnancy maintenance in mares.The number and variety of research topics funded within a single grant cycle is highly unusual and reflects the scope and expected world-wide impact of the research conducted in the Department of Veterinary Sciences, said associate dean for researchJames Matthews.Projects at a glanceFoal health is central to a $650,000 project led byFeng Li, who will study antigenic and genetic diversity in equine rotaviruses. Equine rotavirus A is a major cause of severe diarrhea in foals under six months old and can become rapidly fatal if left untreated. Annual outbreaks during foaling season create health and economic concerns for breeding farms.Lis project will develop genetic tools to isolate and study equine rotaviruses, examine how the viruses change over time and determine how those changes affect the immune systems ability to recognize and fight infection. The work could help guide next-generation vaccine strategies for equine rotavirus and related diseases in other agricultural animals.In that same vein,Yosra Helmy, principal investigator of a $300,000 project, will study alternatives to classical antibiotics for treating subclinical R. equipneumonia in foals. The bacterial disease can cause serious illness and losses on horse farms, and treatment has become more difficult as some strains respond poorly to current antibiotics. With few vaccines available, Helmys team will test small molecules that stopped R. equi growth in early laboratory work and study how well they prevent the bacteria from infecting equine lung immune cells.The goal is to identify safer, more effective treatment candidates while reducing reliance on traditional antibiotics.Allen Pagewill lead a $300,000 study examining whether intra-articular corticosteroid injections affect horses response to vaccination. Corticosteroids are commonly used in joints to treat pain and inflammation, but these drugs can affect immune function. Pages team will test whether administering a joint corticosteroid injection at the same time as a booster vaccine reduces vaccine protection and increases susceptibility to illness after influenza exposure.The findings could help veterinarians better time treatments and vaccines for horses that travel, compete or breed situations where infectious disease outbreaks can be costly and disruptive.Another $300,000 award, led byBruno Menarim, will examine the hidden link between anti-inflammatory drugs and chronic musculoskeletal inflammation in horses. Musculoskeletal conditions are among the leading causes of loss in the horse industry and carry major welfare and financial costs. Menarims project will focus on phenylbutazone, a commonly used non-steroidal anti-inflammatory drug, and whether it interferes with the inflammatory processes horses need for exercise adaptation and recovery.The study will use horses exposed to increasing exercise and experimental joint inflammation to measure how phenylbutazone affects the bodys ability to adapt to training and resolve inflammation.Hossam Elsayedwill lead a $300,000 project focused on one of equine reproductions long-standing unanswered questions: how the early horse embryo signals pregnancy to the mare. Successful pregnancy depends on maternal recognition of pregnancy, a process in which the embryo sends a biochemical message that helps the mare maintain the corpus luteum, a temporary ovarian structure that produces progesterone.Elsayeds project will test whether a hormone, known as CG-beta, may be that signal in horses. Since early pregnancy loss is a major concern in the horse breeding industry, identifying this signal could lead to better pregnancy tests and future treatments to reduce losses.Together, the five projects represent a wide look at horse health, from the first weeks of a foals life to reproductive success, disease prevention and athletic soundness and illustrates the comprehensive equine research capacity possessed by the faculty and facilities of the Department of Veterinary Sciences, Matthews said.This material is based upon work that is supported by the National Institute of Food and Agriculture, U.S. Department of Agriculture under award numbers 2025-67016-44998, 2026-67016-46035, 2026-67016-45719, 2026-67016-45794 and 2026-67016-45712. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture.

According to the attending veterinarian, one horse at a private facility in Randolph County, West Virginia, has tested positive for strangles. The horse is quarantined.EDCC Health Watch is an Equine Network marketing program that utilizes information from the Equine Disease Communication Center (EDCC) to create and disseminate verified equine disease reports. TheEDCCis an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.About StranglesStranglesin horses is an infection caused byStreptococcus equisubspeciesequiand spread through direct contact with other equids or contaminated surfaces. Horses that arent showing clinical signs can harbor and spread the bacteria, and recovered horses remain contagious for at least six weeks, with the potential to cause outbreaks long-term.Infected horses can exhibit a variety of clinical signs:FeverSwollen and/or abscessed lymph nodesNasal dischargeCoughing or wheezingMuscle swellingDifficulty swallowingVeterinarians diagnose horses using polymerase chain reaction (PCR) testing with either a nasal swab, wash, or an abscess sample, and they treat most cases based on clinical signs, implementing antibiotics for severe cases. Overuse of antibiotics can prevent an infected horse from developing immunity. Most horses make a full recovery in three to four weeks.A vaccine is available but not always effective. Biosecurity measures of quarantining new horses at a facility and maintaining high standards of hygiene and disinfecting surfaces can helplower the risk of outbreakorcontain one when it occurs.

Photo: Michelle N. Anderson/The HorseEquine skin problemscan stem from a wide range of causes, including parasites, bacterial or fungal infections, allergies, and prolonged exposure to moisture or irritants. Successfullymanaging horses with skin problemsreliesonworking with your veterinarian toidentifythe underlying issue andappropriately treat it. Because many dermatologic conditions can look similar in theearly stages,itsimportant to have the veterinarianevaluate yourhorsepromptlyto help prevent complications and improve outcomes.Register now and submit your questions for our free Ask TheHorse Live event.Register NowAsk The Horse Live begins on Thursday, June 11, 2026 at 8:00 p.m. EDT Days Hours MinutesAbout the Experts: Julia Miller, DVM, Dipl. ACVD Julia Miller, DVM, Dipl. ACVD, was equine-focused in veterinary school at Cornell University, in Ithaca, New York, and completed a rotating large animal internship at the University of Georgia, in Athens, after graduation. She then went on to be a mixed animal general practitioner for several years before finding her true love, dermatology, and heading back to Cornell for her residency. She now practices in the beautiful land of the bluegrass in Louisville and Lexington, Kentucky and loves working on all creatures great and small! Carly Turner-Garcia, DVM, Dipl. ACT Carly Turner-Garcia, DVM, Dipl. ACT, spent her earlier years working in exotic and small animal veterinary medicine before finding her passion for horses during undergraduate studies at Berry College, in Mount Berry, Georgia. She graduated from The University of Georgias College of Veterinary Medicine, in Athens, continued to an internship at Rood & Riddle Equine Hospital in Lexington, Kentucky, and a residency in theriogenology at Texas A&M University, in College Station, where she earned her Dipl. ACT. She spent the next 10 years in private practice in Weatherford, Texas, and Guthrie, Oklahoma, seeing everything from critical neonatal cases to orthopedic emergencies with a heavy caseload of advanced reproduction. She recently joined the team at Creative Science as a technical services veterinarian while operating her own practice, Black Type Equine, focusing on advanced equine reproduction throughout the U.S. Her biggest joy comes from spending time with her husband, Taylor Garcia, PhD, and their two boys on their ranch in Oklahoma raising cattle, Quarter Horses, and working dogs.

On May 22, the National Veterinary Services Laboratories in Ames, Iowa, confirmed vesicular stomatitis New Jersey virus (VSNJV) on an equine premises in Sandoval County, New Mexico. One horse out of three on the premises had compatible clinical signs and was VSNJV-positive by both polymerase chain reaction (PCR) on swabs of the lesions and competitive enzyme-linked immunosorbent assay (cELISA) on serology.This is the index case of VSV for New Mexico in 2026. Since the index case was confirmed, horses at a second equine premises in Sandoval County have developed clinical signs of VSV and are presumed to be positive without testing.Since October 2025, VSV has been identified at 15 equine premises in Arizona and one equine premises in Colorado. All confirmed caseshave been vesicular stomatitis New Jersey virus (VSNJV) serotype.The last outbreak of VSV in the U.S. occurred from May 2023 through January 2024, affecting 319 premises across California, Nevada, and Texas. VSV circulates annually between livestock and insect vectors in southern Mexico and only occasionally results in incursion to the U.S.EDCC Health Watch is an Equine Network marketing program that utilizes information from the Equine Disease Communication Center (EDCC) to create and disseminate verified equine disease reports. TheEDCCis an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.About Vesicular StomatitisVesicular stomatitis is a viral disease of horses, donkeys, mules, cattle, swine and New World camelids that occurs in the Western Hemisphere. It is named for the characteristic vesicular lesions it causes in the form of blisters, crusts and ulceration of the lips, muzzle, nose, tongue, ears, sheath, teats and/or coronary band. The virus is transmitted by biting midges and therefore is seasonal.Clinical Signs for vesicular stomatitis include:Vesicle formation leading to ulcerative lesions on the lips, muzzle, nostrils and tongue. The tongue is often the most severely affected area.Ulceration of the inner surface of the lips.Crusting of the muzzle, nostrils, and/or inside the ears.Excessive salivation secondary to the oral lesions.Difficulty picking up and chewing feed.Lameness due to painful erosions on the coronary band.Lesions can occur on the udder, sheath and inside of the ear.Lesions can develop secondary infections resulting in slow-to-heal wounds.Animals on pastures are at increased risk of vesicular stomatitis.Initial diagnosis is based on recognition of characteristic vesicular lesions. Infection is confirmed via laboratory testing for serum antibodies and/or virus identification in fluid samples from active lesions. Veterinarians are required to report suspected cases to state/federal animal health officials who will direct sample submission to an approved regulatory laboratory for diagnostic testing.There is no specific treatment for vesicular stomatitis. Best practices include implementing good biosecurity and treating affected horses with pain relievers, anti-inflammatories and supportive care as recommended by a veterinarian.Isolating all affected animals and placing the premise on immediate quarantine is required until all horses have fully recovered and no active lesions are present. The State Veterinarian will work with the local veterinarian to determine and implement necessary quarantine procedures.