On May 30, a 14-year-old mare at a boarding facility in Seminole County, Florida, tested positive for strangles. The horse developed clinical signs on April 11, including fever and nasal discharge. She is now recovering. 

In addition to the confirmed case, four horses are suspected positive, and 30 horses are 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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Strangles

Strangles in horses is an infection caused by Streptococcus equi subspecies equi and spread through direct contact with other equids or contaminated surfaces. Horses that aren’t 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:

• Fever
• Swollen and/or abscessed lymph nodes
• Nasal discharge
• Coughing or wheezing
• Muscle swelling
• Difficulty swallowing

Veterinarians 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 help lower the risk of outbreak or contain one when it occurs.

One horse at a private facility in Whatcom County, Washington, recently tested positive for pigeon fever. The horse had been colicky and nonresponsive and was euthanized. Necropsy revealed massive internal adhesions and abscessation.

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Pigeon Fever

Pigeon fever is a bacterial infection that affects cattle and horses. It can cause large abscesses, most commonly on the chest and under the belly. Horses become infected when bacteria enters through broken skin, such as small scrapes or wounds. Peak season for infection is late summer through fall.

Good horse health safety practices are key to limiting the spread of pigeon fever. These practices include:

• Fly control;
• Not sharing water buckets or equipment; and
• Avoiding tying horses in high-traffic areas.

If a horse owner suspects that their animal is affected, they should contact their veterinarian.

On June 3, a 23-year-old pony mare in Sonoma County, California, tested positive for equine herpesvirus myeloencephalopathy (EHM) secondary to equine herpesvirus-1 (EHV-1). The mare initially became ataxia on June 1. She was euthanized, and 36 potentially exposed horses on the home premises are under quarantine. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

EHV 101

Herpesvirus 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.

One foal at a stable in Estrie, Quebec, recently tested positive for rotavirus after presenting with diarrhea. It is unknown if other horses are 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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

On May 28, one horse in Clearwater County, Alberta, was confirmed positive for equine infectious anemia (EIA). The horse was tested after developing clinical signs of disease. Initial reports indicate that there are several other horses on the property. The infected horse and all exposed horses are under quarantine. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About EIA

Equine infectious anemia is a viral disease that attacks horses’ immune systems. The virus is transmitted through the exchange of body fluids from an infected to an uninfected animal, often by blood-feeding insects such as horseflies. It can also be transmitted through the use of blood-contaminated instruments or needles.

A Coggins test screens horses’ blood for antibodies that are indicative of the presence of the EIA virus. Most U.S. states require horses to have proof of a negative Coggins test to travel across state lines.

Once an animal is infected with EIA, it is infected for life and can be a reservoir for the spread of disease. Not all horses show signs of disease, but those that do can exhibit:

• Progressive body condition loss;
• Muscle weakness;
• Poor stamina;
• Fever;
• Depression; and
• Anemia.

EIA has no vaccine and no cure. A horse diagnosed with the disease dies, is euthanized, or must be placed under extremely strict quarantine conditions (at least 200 yards away from unaffected equids) for the rest of his life.

On May 29, a 2-year-old Thoroughbred colt in Barn 85 at the Saratoga Race Course in Saratoga County, New York, tested positive for strangles. The horse was shipped to Rood & Riddle Equine Hospital on May 28 for evaluation and treatment of a respiratory infection. He began treatment immediately and was transported from the hospital to a private layup facility. 

Barn 85 is now under quarantine. A 24-hour security watch has been established, and all horses in the barn will receive regular temperature checks. The horses under quarantine are not permitted to enter races or train among the general horse population. Asymptomatic horses in Barn 85 will have isolated training hours at the Oklahoma Training Track following the close of training for the general horse population at 10 a.m. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Strangles

Strangles in horses is an infection caused by Streptococcus equi subspecies equi and spread through direct contact with other equids or contaminated surfaces. Horses that aren’t 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:

• Fever
• Swollen and/or abscessed lymph nodes
• Nasal discharge
• Coughing or wheezing
• Muscle swelling
• Difficulty swallowing

Veterinarians 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 help lower the risk of outbreak or contain one when it occurs.

The State Department of Agriculture recently confirmed that one horse in Hall County, Georgia, is positive for pigeon fever. The horse is under voluntary quarantine. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Pigeon Fever

Pigeon fever is a bacterial infection that affects cattle and horses. It can cause large abscesses, most commonly on the chest and under the belly. Horses become infected when bacteria enters through broken skin, such as small scrapes or wounds. Peak season for infection is late summer through fall.

Good horse health safety practices are key to limiting the spread of pigeon fever. These practices include:

• Fly control;
• Not sharing water buckets or equipment; and
• Avoiding tying horses in high-traffic areas.

If a horse owner suspects that their animal is affected, they should contact their veterinarian.

A 2-week-old foal in Région de Gatineau, Quebec, recently tested positive for rotavirus after developing diarrhea and hepatitis. The foal is recovering, and one additional case is suspected. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

On May 24, a 26-year-old Arabian gelding at a boarding facility in Niagara County, New York, tested positive for strangles. The horse developed clinical signs on May 21, including fever and inappetence. Two additional cases are suspected, and 15 horses are 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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Strangles

Strangles in horses is an infection caused by Streptococcus equi subspecies equi and spread through direct contact with other equids or contaminated surfaces. Horses that aren’t 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:

• Fever
• Swollen and/or abscessed lymph nodes
• Nasal discharge
• Coughing or wheezing
• Muscle swelling
• Difficulty swallowing

Veterinarians 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 help lower the risk of outbreak or contain one when it occurs.

On May 22, a 6-year-old Mustang gelding in Eaton County, Michigan, tested positive for strangles. The horse developed clinical signs on May 12, including nasal discharge and swollen submandibular lymph nodes. He is now under quarantine. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Strangles

Strangles in horses is an infection caused by Streptococcus equi subspecies equi and spread through direct contact with other equids or contaminated surfaces. Horses that aren’t 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:

• Fever
• Swollen and/or abscessed lymph nodes
• Nasal discharge
• Coughing or wheezing
• Muscle swelling
• Difficulty swallowing

Veterinarians 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 help lower the risk of outbreak or contain one when it occurs.

On May 22, a 20-year-old Quarter Horse mare in Cumberland County, Pennsylvania, tested positive for Potomac horse fever. The horse, who is vaccinated, developed clinical signs on May 18, including fever and colic signs which progressed to liquid diarrhea. She was referred to a hospital in Virginia, where she is responding to medical management.

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Potomac Horse Fever

Potomac horse fever is caused by Neorickettsia risticii, an organism found in parasites, called flukes (flatworms), that infects aquatic snails and insects. Horses can be infected by ingesting insects carrying Potomac horse fever or by drinking water containing N. risticii. Additionally, horses can get Potomac horse fever by inadvertently consuming infected insects or parasites in feed, water, or on pasture.

The incubation period for Potomac horse fever is between one and three weeks, and the mortality rate is up to 30%. While vaccines against Potomac horse fever are not 100% effective, vaccinated horses tend to have fewer and less severe clinical signs.

Most Potomac horse fever cases are reported in July through September, and outbreaks tend to be seasonal.

Horse owners and caretakers, especially those who keep their horses near creeks and rivers, should watch for signs including:

• Diarrhea
• Colic
• Loss of appetite
• Lethargy
• Toxic shock
• Dehydration
• Abortion in pregnant mares
• Laminitis
• Mild to severe fever.

Three horses at a boarding facility in Marion County, Florida, recently tested positive for strangles. The affected horses are under quarantine, and 50 additional horses are 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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Strangles

Strangles in horses is an infection caused by Streptococcus equi subspecies equi and spread through direct contact with other equids or contaminated surfaces. Horses that aren’t 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:

• Fever
• Swollen and/or abscessed lymph nodes
• Nasal discharge
• Coughing or wheezing
• Muscle swelling
• Difficulty swallowing

Veterinarians 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 help lower the risk of outbreak or contain one when it occurs.

On May 22, a 4-year-old Thoroughbred gelding at a boarding facility in Montgomery County, Pennsylvania, tested positive for strangles. The horse developed clinical signs on May 19, including fever and nasal discharge. He is under quarantine, and 39 horses are 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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Strangles

Strangles in horses is an infection caused by Streptococcus equi subspecies equi and spread through direct contact with other equids or contaminated surfaces. Horses that aren’t 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:

• Fever
• Swollen and/or abscessed lymph nodes
• Nasal discharge
• Coughing or wheezing
• Muscle swelling
• Difficulty swallowing

Veterinarians 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 help lower the risk of outbreak or contain one when it occurs.

On May 20, a 25-year-old mare at a boarding facility in the Regional Municipality of Halton, Ontario, tested positive for strangles. The mare developed a thick nasal discharge and cough after sharing a paddock with four new horses. She is now under quarantine. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Strangles

Strangles in horses is an infection caused by Streptococcus equi subspecies equi and spread through direct contact with other equids or contaminated surfaces. Horses that aren’t 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:

• Fever
• Swollen and/or abscessed lymph nodes
• Nasal discharge
• Coughing or wheezing
• Muscle swelling
• Difficulty swallowing

Veterinarians 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 help lower the risk of outbreak or contain one when it occurs.

Two horses in Florida recently tested positive for strangles. The horses live in Charlotte and Walton counties. 

In Charlotte County, a 14-year-old Quarter Horse gelding tested positive on May 20 after developing nasal discharge. He is under quarantine, and one additional horse is suspected positive. 

In Walton County, an 8-year-old Thoroughbred gelding tested positive on May 20 after developing a lymph node abscess on May 15. One additional horse is suspected positive, and four horses are 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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Strangles

Strangles in horses is an infection caused by Streptococcus equi subspecies equi and spread through direct contact with other equids or contaminated surfaces. Horses that aren’t 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:

• Fever
• Swollen and/or abscessed lymph nodes
• Nasal discharge
• Coughing or wheezing
• Muscle swelling
• Difficulty swallowing

Veterinarians 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 help lower the risk of outbreak or contain one when it occurs.

Six horses at a premises in Los Angeles County, California, recently tested positive for equine herpesvirus-1 (EHV-1). 

Two horses—a 20-year-old Thoroughbred mare and a 28-year-old warmblood mare—were reported positive on May 16. The 20-year-old mare was euthanized, and 95 exposed horses were placed under quarantine. 

Since then, four additional horses have tested positive, including a 3-year-old gelding, a 20-year-old mare, a 21-year-old warmblood mare, and a 24-year-old Quarter Horse mare. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

EHV 101

Herpesvirus 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.

One horse at a private facility in King County, Washington, recently tested positive for pigeon fever. No additional details are currently available. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Pigeon Fever

Pigeon fever is a bacterial infection that affects cattle and horses. It can cause large abscesses, most commonly on the chest and under the belly. Horses become infected when bacteria enters through broken skin, such as small scrapes or wounds. Peak season for infection is late summer through fall.

Good horse health safety practices are key to limiting the spread of pigeon fever. These practices include:

• Fly control;
• Not sharing water buckets or equipment; and
• Avoiding tying horses in high-traffic areas.

If a horse owner suspects that their animal is affected, they should contact their veterinarian.

One horse at a stable in Mirabel, Quebec, recently tested positive for equine influenza after developing a cough and light nasal discharge. The horse is under quarantine. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Equine Influenza

Equine influenza is 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 106°F); a dry, hacking cough; depression; weakness; anorexia; serous (watery) nasal discharge; and slightly enlarged lymph nodes. Consider monitoring your horse’s 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.

​Vaccination is 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 strict biosecurity protocols can help reduce your horse’s 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.

A 27-year-old Arabian mare at a boarding facility in Dane County, Wisconsin, recently tested positive for strangles after developing clinical signs on May 8. She is under quarantine, and 50 horses are potentially 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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Strangles

Strangles in horses is an infection caused by Streptococcus equi subspecies equi and spread through direct contact with other equids or contaminated surfaces. Horses that aren’t 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:

• Fever
• Swollen and/or abscessed lymph nodes
• Nasal discharge
• Coughing or wheezing
• Muscle swelling
• Difficulty swallowing

Veterinarians 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 help lower the risk of outbreak or contain one when it occurs.

One horse in Grays Harbor County, Washington, recently tested positive for strangles. The horse lives at a private facility, and it is unknown if additional horses are 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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Strangles

Strangles in horses is an infection caused by Streptococcus equi subspecies equi and spread through direct contact with other equids or contaminated surfaces. Horses that aren’t 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:

• Fever
• Swollen and/or abscessed lymph nodes
• Nasal discharge
• Coughing or wheezing
• Muscle swelling
• Difficulty swallowing

Veterinarians 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 help lower the risk of outbreak or contain one when it occurs.

On April 29, a 5-year-old Quarter Horse mare used for barrel racing in Garvin County, Oklahoma, tested positive for equine infectious anemia (EIA). The horse was tested due to a trace from an off-premises exposure. She was euthanized, and 38 additional horses are potentially 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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About EIA

Equine infectious anemia is a viral disease that attacks horses’ immune systems. The virus is transmitted through the exchange of body fluids from an infected to an uninfected animal, often by blood-feeding insects such as horseflies. It can also be transmitted through the use of blood-contaminated instruments or needles.

A Coggins test screens horses’ blood for antibodies that are indicative of the presence of the EIA virus. Most U.S. states require horses to have proof of a negative Coggins test to travel across state lines.

Once an animal is infected with EIA, it is infected for life and can be a reservoir for the spread of disease. Not all horses show signs of disease, but those that do can exhibit:

• Progressive body condition loss;
• Muscle weakness;
• Poor stamina;
• Fever;
• Depression; and
• Anemia.

EIA has no vaccine and no cure. A horse diagnosed with the disease dies, is euthanized, or must be placed under extremely strict quarantine conditions (at least 200 yards away from unaffected equids) for the rest of his life.

On May 6, a 4-year-old Paint mare in Rogers County, Oklahoma, tested positive for equine herpesvirus-1 (EHV-1). She developed clinical signs on May 2, including hind limb weakness, urine retention, and recumbency. The mare was euthanized, and 10 exposed horses are under quarantine.

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

EHV 101

Herpesvirus 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.

Two horses in Los Angeles County, California, recently tested positive for equine herpesvirus-1 (EHV-1). 

The first horse was a 20-year-old Thoroughbred mare, who eventually developed equine myeloencephalopathy (EHM) secondary to EHV-1 infection. The mare was euthanized. 

The second horse is a 28-year-old warmblood mare who tested positive for EHV-1 after developing a fever. She is still alive. 

In addition to the two confirmed cases, 95 horses on the premises are potentially exposed. They are quarantined, and the California Department of Food and Agriculture is actively monitoring the situation.

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

EHV 101

Herpesvirus 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.

A 7-year-old Quarter Horse gelding in Wellington County, Ontario, recently tested positive for equine influenza. The horse was at a barrel racing event in Huron County and developed a fever after returning home on May 11. He is now recovering, and two additional cases are suspected. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Equine Influenza

Equine influenza is 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 106°F); a dry, hacking cough; depression; weakness; anorexia; serous (watery) nasal discharge; and slightly enlarged lymph nodes. Consider monitoring your horse’s 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.

​Vaccination is 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 strict biosecurity protocols can help reduce your horse’s 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 8, a yearling Paint colt in Eaton County, Michigan, tested positive for strangles. The colt developed clinical signs on March 28, including fever and enlarged lymph nodes. He is now under quarantine.

Two ponies on the same premises previously tested positive for strangles in February. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Strangles

Strangles in horses is an infection caused by Streptococcus equi subspecies equi and spread through direct contact with other equids or contaminated surfaces. Horses that aren’t 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:

• Fever
• Swollen and/or abscessed lymph nodes
• Nasal discharge
• Coughing or wheezing
• Muscle swelling
• Difficulty swallowing

Veterinarians 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 help lower the risk of outbreak or contain one when it occurs.

On May 5, a 7-year-old Thoroughbred gelding in Marion County, Florida, tested positive for strangles. The horse is under quarantine, and one additional horse is exposed.

This is Florida’s 18^th confirmed strangles case in 2025. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Strangles

Strangles in horses is an infection caused by Streptococcus equi subspecies equi and spread through direct contact with other equids or contaminated surfaces. Horses that aren’t 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:

• Fever
• Swollen and/or abscessed lymph nodes
• Nasal discharge
• Coughing or wheezing
• Muscle swelling
• Difficulty swallowing

Veterinarians 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 help lower the risk of outbreak or contain one when it occurs.

On May 2, a 2-year-old filly in Buffalo County, Wisconsin, tested positive for strangles. The filly developed clinical signs on March 28, including fever and submandibular lymph node abscess. She is under quarantine, and two additional horses are 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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Strangles

Strangles in horses is an infection caused by Streptococcus equi subspecies equi and spread through direct contact with other equids or contaminated surfaces. Horses that aren’t 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:

• Fever
• Swollen and/or abscessed lymph nodes
• Nasal discharge
• Coughing or wheezing
• Muscle swelling
• Difficulty swallowing

Veterinarians 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 help lower the risk of outbreak or contain one when it occurs.

The North Carolina Department of Agriculture’s Veterinary Division recently confirmed that one horse in Beaufort County has tested positive for strangles. No additional details are currently available. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Strangles

Strangles in horses is an infection caused by Streptococcus equi subspecies equi and spread through direct contact with other equids or contaminated surfaces. Horses that aren’t 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:

• Fever
• Swollen and/or abscessed lymph nodes
• Nasal discharge
• Coughing or wheezing
• Muscle swelling
• Difficulty swallowing

Veterinarians 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 help lower the risk of outbreak or contain one when it occurs.

On May 5, two horses in St. Clair County, Michigan—a 5-year-old Paint gelding and a 5-year-old warmblood gelding—tested positive for strangles. Both horses developed clinical signs on April 24, including fever and nasal discharge. They are under quarantine. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Strangles

Strangles in horses is an infection caused by Streptococcus equi subspecies equi and spread through direct contact with other equids or contaminated surfaces. Horses that aren’t 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:

• Fever
• Swollen and/or abscessed lymph nodes
• Nasal discharge
• Coughing or wheezing
• Muscle swelling
• Difficulty swallowing

Veterinarians 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 help lower the risk of outbreak or contain one when it occurs.

Two horses in Maryland—one in Carroll County and one in Cecil County—recently tested positive for strangles. In addition to the two confirmed cases, 20 horses in Carroll County and 50 horses in Cecil County are potentially 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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Strangles

Strangles in horses is an infection caused by Streptococcus equi subspecies equi and spread through direct contact with other equids or contaminated surfaces. Horses that aren’t 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:

• Fever
• Swollen and/or abscessed lymph nodes
• Nasal discharge
• Coughing or wheezing
• Muscle swelling
• Difficulty swallowing

Veterinarians 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 help lower the risk of outbreak or contain one when it occurs.

One horse in Chesterfield County, Virginia, recently tested positive for equine infectious anemia (EIA) during a routine Coggins test. The horse is quarantined on the property and reportedly does not pose a risk to other horses in the area. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About EIA

Equine infectious anemia is a viral disease that attacks horses’ immune systems. The virus is transmitted through the exchange of body fluids from an infected to an uninfected animal, often by blood-feeding insects such as horseflies. It can also be transmitted through the use of blood-contaminated instruments or needles.

A Coggins test screens horses’ blood for antibodies that are indicative of the presence of the EIA virus. Most U.S. states require horses to have proof of a negative Coggins test to travel across state lines.

Once an animal is infected with EIA, it is infected for life and can be a reservoir for the spread of disease. Not all horses show signs of disease, but those that do can exhibit:

• Progressive body condition loss;
• Muscle weakness;
• Poor stamina;
• Fever;
• Depression; and
• Anemia.

EIA has no vaccine and no cure. A horse diagnosed with the disease dies, is euthanized, or must be placed under extremely strict quarantine conditions (at least 200 yards away from unaffected equids) for the rest of his life.

Two horses in Ontario recently tested positive for strangles. The horses live in Dufferin and Brant counties. 

In Dufferin County, a 12-year-old warmblood gelding developed an abscess on the outside aspect of his jaw, which was positive for S. equi. The horse is under voluntary quarantine. 

In Brant County, a 7-year-old Quarter Horse gelding developed a fever and nasal discharge shortly after returning from a competition in the Hamilton region. The nasal discharge tested positive for S. equi. One other horse on the property has since developed clinical signs. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Strangles

Strangles in horses is an infection caused by Streptococcus equi subspecies equi and spread through direct contact with other equids or contaminated surfaces. Horses that aren’t 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:

• Fever
• Swollen and/or abscessed lymph nodes
• Nasal discharge
• Coughing or wheezing
• Muscle swelling
• Difficulty swallowing

Veterinarians 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 help lower the risk of outbreak or contain one when it occurs.

Seventeen horses in Texas recently tested positive for equine infectious anemia (EIA), including six in Wise County, one in Montague County, one in Hood County, one in Wharton County, five in Brazos County, one in Van Zandt County, and two in Cooke County. 

The positive horses have all either been quarantined or euthanized. The Texas Animal Health Commission is working closely with the owners and local veterinarians to monitor potentially exposed horses and implement biosecurity measures. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About EIA

Equine infectious anemia is a viral disease that attacks horses’ immune systems. The virus is transmitted through the exchange of body fluids from an infected to an uninfected animal, often by blood-feeding insects such as horseflies. It can also be transmitted through the use of blood-contaminated instruments or needles.

A Coggins test screens horses’ blood for antibodies that are indicative of the presence of the EIA virus. Most U.S. states require horses to have proof of a negative Coggins test to travel across state lines.

Once an animal is infected with EIA, it is infected for life and can be a reservoir for the spread of disease. Not all horses show signs of disease, but those that do can exhibit:

• Progressive body condition loss;
• Muscle weakness;
• Poor stamina;
• Fever;
• Depression; and
• Anemia.

EIA has no vaccine and no cure. A horse diagnosed with the disease dies, is euthanized, or must be placed under extremely strict quarantine conditions (at least 200 yards away from unaffected equids) for the rest of his life.

One horse at a private facility in Challam County, Washington, recently tested positive for equine influenza. The horse is under quarantine, and two additional cases are suspected.  

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Equine Influenza

Equine influenza is 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 106°F); a dry, hacking cough; depression; weakness; anorexia; serous (watery) nasal discharge; and slightly enlarged lymph nodes. Consider monitoring your horse’s 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.

​Vaccination is 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 strict biosecurity protocols can help reduce your horse’s 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 1, a gelding at a private facility in Orange County, Florida, tested positive for strangles. The horse developed clinical signs on April 23, including nasal discharge and fever. He is under official quarantine.

This is Florida’s 17^th confirmed strangles case in 2025. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Strangles

Strangles in horses is an infection caused by Streptococcus equi subspecies equi and spread through direct contact with other equids or contaminated surfaces. Horses that aren’t 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:

• Fever
• Swollen and/or abscessed lymph nodes
• Nasal discharge
• Coughing or wheezing
• Muscle swelling
• Difficulty swallowing

Veterinarians 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 help lower the risk of outbreak or contain one when it occurs.

On April 23, a weanling colt in Ingham County, Michigan, tested positive for strangles after developing a fever and nasal discharge. He is under voluntary quarantine. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Strangles

Strangles in horses is an infection caused by Streptococcus equi subspecies equi and spread through direct contact with other equids or contaminated surfaces. Horses that aren’t 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:

• Fever
• Swollen and/or abscessed lymph nodes
• Nasal discharge
• Coughing or wheezing
• Muscle swelling
• Difficulty swallowing

Veterinarians 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 help lower the risk of outbreak or contain one when it occurs.

On April 22, a 16-year-old Quarter Horse mare at a boarding facility in Washington County, Minnesota, tested positive for equine herpesvirus-1 (EHV-1). The mare developed clinical signs on April 22, including ataxia and urine dribbling. She is under quarantine, and 30 horses are potentially 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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

EHV 101

Herpesvirus 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.

Three horses in Washington recently tested positive for equine influenza. The horses live in Spokane and Kittitas counties. 

In Spokane County, two horses at a boarding facility are positive, and eight horses are suspected positive. The affected horses are under veterinary care. 

In Kittitas County, one horse at a private facility is positive, and three horses are suspected positive. The affected horse is under veterinary care. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Equine Influenza

Equine influenza is 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 106°F); a dry, hacking cough; depression; weakness; anorexia; serous (watery) nasal discharge; and slightly enlarged lymph nodes. Consider monitoring your horse’s 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.

​Vaccination is 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 strict biosecurity protocols can help reduce your horse’s 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 April 17, a yearling donkey in Lake County, Florida, tested positive for Eastern equine encephalitis (EEE) after developing clinical signs on April 3. The donkey is now deceased. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

EEE 101

Eastern equine encephalomyelitis is caused by the Eastern equine encephalitis virus, for which wild birds are a natural reservoir. Mosquitoes that feed on EEE-infected birds can transmit the virus to humans, horses, and other birds. Horses do not develop high enough levels of these viruses in their blood to be contagious to other animals or humans. Because of the high mortality rate in horses and humans, EEE is regarded as one of the most serious mosquito-borne diseases in the United States.

Tips for preventing mosquito-borne diseases include:

• Avoid mosquito bites: Use insect repellent when outdoors, especially from dusk to dawn.
• Look for EPA-labeled products containing active ingredients such as DEET, picaridin (KBR3023), or oil of lemon eucalyptus (p-menthane 3,8-diol).
• Apply more repellent, according to label instructions, if mosquitoes start to bite.
• Mosquito-proof homes: Fix or install window and door screens, and cover or eliminate empty containers with standing water where mosquitoes can lay eggs.
• Protect your horses: Veterinarians recommend commercially available licensed vaccines against EEE for all horses in the U.S. Horses should be vaccinated at least annually (recommendations vary in high-risk areas). It’s not too late this year to vaccinate your horses.
• Use approved insect repellents to protect horses.
• If possible, put horses in stables, stalls, or barns during the prime mosquito exposure hours of dusk and dawn.
• Eliminate standing water, drain water troughs, and empty buckets at least weekly.
• Stock water tanks with fish that consume mosquito larvae (contact your local mosquito control for assistance), or use mosquito “dunks” (solid “donuts” of Bacillus thuringiensis israelensis, which are nontoxic to horses) available at hardware stores.

A 7-year-old mare in MRC Les Collines-de-l’Outaouais, Quebec, recently tested positive for equine influenza after developing a fever, cough, and nasal discharge. She is under voluntary quarantine. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Equine Influenza

Equine influenza is 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 106°F); a dry, hacking cough; depression; weakness; anorexia; serous (watery) nasal discharge; and slightly enlarged lymph nodes. Consider monitoring your horse’s 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.

​Vaccination is 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 strict biosecurity protocols can help reduce your horse’s 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.

A 12-year-old Quarter Horse mare in Madera County, California, recently tested positive for equine infectious anemia (EIA). The mare was exposed to EIA out of state and was detected as part of an epidemiological trace out. 

Eight potentially exposed horses on the mare’s home premises have tested negative for EIA and will remain under quarantine until their 60-day retest. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About EIA

Equine infectious anemia is a viral disease that attacks horses’ immune systems. The virus is transmitted through the exchange of body fluids from an infected to an uninfected animal, often by blood-feeding insects such as horseflies. It can also be transmitted through the use of blood-contaminated instruments or needles.

A Coggins test screens horses’ blood for antibodies that are indicative of the presence of the EIA virus. Most U.S. states require horses to have proof of a negative Coggins test to travel across state lines.

Once an animal is infected with EIA, it is infected for life and can be a reservoir for the spread of disease. Not all horses show signs of disease, but those that do can exhibit:

• Progressive body condition loss;
• Muscle weakness;
• Poor stamina;
• Fever;
• Depression; and
• Anemia.

EIA has no vaccine and no cure. A horse diagnosed with the disease dies, is euthanized, or must be placed under extremely strict quarantine conditions (at least 200 yards away from unaffected equids) for the rest of his life.

One horse in New York recently tested positive for equine herpesvirus-1 (EHV-1). The horse arrived at showgrounds in Erie County on Wednesday, April 23, became symptomatic on Thursday, and was diagnosed on Friday. The horse was euthanized. 

Five horses that trailered in with this horse were quickly removed from the showgrounds and are quarantined at the home premises. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

EHV 101

Herpesvirus 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.

On April 25, a 15-year-old Thoroughbred mare at a training facility in St. Croix County, Wisconsin, tested positive for equine herpesvirus-1 (EHV-1) after developing neurologic signs on April 21. The mare is under quarantine.

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

EHV 101

Herpesvirus 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.

On April 22, a 17-year-old pony mare in Putnam County, Florida, tested positive for strangles after developing a fever. She is now recovering, and two additional horses are exposed. 

This is Florida’s 15^th confirmed case of strangles in 2025. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Strangles

Strangles in horses is an infection caused by Streptococcus equi subspecies equi and spread through direct contact with other equids or contaminated surfaces. Horses that aren’t 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:

• Fever
• Swollen and/or abscessed lymph nodes
• Nasal discharge
• Coughing or wheezing
• Muscle swelling
• Difficulty swallowing

Veterinarians 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 help lower the risk of outbreak or contain one when it occurs.

On March 21, a 6-year-old Quarter Horse gelding in Rock County, Wisconsin, tested positive for strangles after developing clinical signs on March 18. The horse is under quarantine, and 20 horses are 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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Strangles

Strangles in horses is an infection caused by Streptococcus equi subspecies equi and spread through direct contact with other equids or contaminated surfaces. Horses that aren’t 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:

• Fever
• Swollen and/or abscessed lymph nodes
• Nasal discharge
• Coughing or wheezing
• Muscle swelling
• Difficulty swallowing

Veterinarians 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 help lower the risk of outbreak or contain one when it occurs.

A yearling Quarter Horse colt in the District of Temiskaming, Ontario, recently tested positive for strangles. The horse was purchased from a farm in southern Ontario and was paired with a gelding upon arrival at his new farm. About 10 days later, he developed swollen lymph nodes, nasal discharge, and fever and tested positive for S. equi. He is now under quarantine.

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Strangles

Strangles in horses is an infection caused by Streptococcus equi subspecies equi and spread through direct contact with other equids or contaminated surfaces. Horses that aren’t 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:

• Fever
• Swollen and/or abscessed lymph nodes
• Nasal discharge
• Coughing or wheezing
• Muscle swelling
• Difficulty swallowing

Veterinarians 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 help lower the risk of outbreak or contain one when it occurs.

An Appaloosa gelding in Hastings County, Ontario, recently tested positive for equine influenza. The horse was purchased from an auction in Northumberland County and developed a cough and nasal discharge the following day. Four additional horses on the property have been vaccinated for influenza and only developed mild signs. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Equine Influenza

Equine influenza is 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 106°F); a dry, hacking cough; depression; weakness; anorexia; serous (watery) nasal discharge; and slightly enlarged lymph nodes. Consider monitoring your horse’s 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.

​Vaccination is 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 strict biosecurity protocols can help reduce your horse’s 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.

A 14-year-old Quarter Horse gelding at a boarding facility in Flagler County, Florida, recently tested positive for strangles. The horse developed clinical signs on April 11, including fever, nasal discharge, and cough. He is now recovering, and 14 additional horses are exposed. 

This is Florida’s 14^th confirmed case of strangles in 2025. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Strangles

Strangles in horses is an infection caused by Streptococcus equi subspecies equi and spread through direct contact with other equids or contaminated surfaces. Horses that aren’t 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:

• Fever
• Swollen and/or abscessed lymph nodes
• Nasal discharge
• Coughing or wheezing
• Muscle swelling
• Difficulty swallowing

Veterinarians 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 help lower the risk of outbreak or contain one when it occurs.

On April 8, a 2-year-old Quarter Horse filly in Garvin County, Oklahoma, tested positive for equine infectious anemia (EIA). The filly was not displaying clinical signs and was tested due to a trace from an off-premises exposure. She was euthanized, and 12 exposed horses on the premises are under quarantine. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About EIA

Equine infectious anemia is a viral disease that attacks horses’ immune systems. The virus is transmitted through the exchange of body fluids from an infected to an uninfected animal, often by blood-feeding insects such as horseflies. It can also be transmitted through the use of blood-contaminated instruments or needles.

A Coggins test screens horses’ blood for antibodies that are indicative of the presence of the EIA virus. Most U.S. states require horses to have proof of a negative Coggins test to travel across state lines.

Once an animal is infected with EIA, it is infected for life and can be a reservoir for the spread of disease. Not all horses show signs of disease, but those that do can exhibit:

• Progressive body condition loss;
• Muscle weakness;
• Poor stamina;
• Fever;
• Depression; and
• Anemia.

EIA has no vaccine and no cure. A horse diagnosed with the disease dies, is euthanized, or must be placed under extremely strict quarantine conditions (at least 200 yards away from unaffected equids) for the rest of his life.

On April 16, one horse at a boarding facility in Montgomery County, Maryland, tested positive for strangles. Seventy-three exposed horses were also tested, and three of those horses have since tested positive. The four positive horses are quarantined and will be tested again after 21 days. Staff is monitoring exposed horses daily for new symptoms, and the farm is complying with state quarantine procedures. 

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. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Strangles

Strangles in horses is an infection caused by Streptococcus equi subspecies equi and spread through direct contact with other equids or contaminated surfaces. Horses that aren’t 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:

• Fever
• Swollen and/or abscessed lymph nodes
• Nasal discharge
• Coughing or wheezing
• Muscle swelling
• Difficulty swallowing

Veterinarians 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 help lower the risk of outbreak or contain one when it occurs.