Coggins Test Requirements in Tennessee: What Every Horse Owner Must Know

Tennessee takes equine infectious anemia seriously, and the state’s Coggins test rules reflect that. The Tennessee State Veterinarian has issued alerts about EIA cases — including a 2021 outbreak in Shelby County where two horses tested positive and the affected stable was placed under immediate quarantine. If you own, transport, board, or show a horse in Tennessee, understanding the Coggins test requirements is not optional — it’s the law.

This guide walks you through every layer of Tennessee’s EIA regulations: which animals are covered, when testing is required, how the test works, what happens at state borders, and what the consequences are for a positive result or non-compliance.

What Is Equine Infectious Anemia (EIA) and Why It Is Regulated in Tennessee

The Coggins test is a blood test used to screen horses, mules, and donkeys for Equine Infectious Anemia (EIA), an infectious and potentially deadly virus that affects the immune system of animals in the Equidae family. The disease is sometimes called “swamp fever,” and it has no cure and no approved vaccine.

EIA is caused by a lentivirus in the same family as HIV. The virus targets a type of white blood cell called a macrophage and, once inside the horse’s body, stays there for life. There is no way to clear the infection. An infected horse becomes a permanent carrier, capable of spreading the virus to other horses even when it looks perfectly healthy.

EIA is spread from horse to horse by mosquito bites, horse flies, deer flies, or stable flies that have fed on another infected horse — meaning your horse can contract the disease without ever coming into direct contact with an infected animal. EIA can also be transmitted unintentionally by mechanical means, including transfusion of infective blood or blood-contaminated instruments.

While some horses can carry the virus without showing symptoms, others will experience very serious symptoms such as irregular heartbeats, swollen legs and abdomen, general weakness, anemia, a high fever, and even death. The three recognized clinical forms are acute, chronic, and inapparent carrier — the last being the most dangerous from a public health standpoint because infected horses show no outward signs.

Tennessee regulates EIA because EIA can rapidly spread among equines since insects are naturally attracted to areas where horses congregate, such as barns. EIA is a reportable disease regulated by the United States Department of Agriculture (USDA) and state animal health regulatory agencies. The Tennessee Department of Agriculture enforces the state’s specific rules under Tennessee Department of Agriculture Rule 0080-02-11, which governs handling of positive equines.

Key Insight: EIA does not cause disease in humans, but it is devastating for horses. Because there is no treatment or vaccine, testing and removal of positive animals are the only tools available to protect the broader equine population.

Which Animals Require a Coggins Test in Tennessee

The Coggins test is used to screen horses, mules, and donkeys for EIA. In Tennessee, the requirement applies broadly across the Equidae family. Any animal in the Family Equidae — including horses, asses, mules, ponies, and zebras — falls under the scope of EIA regulations.

In the State of Tennessee, every horse or member of the equine family over the age of 6 months is required to have proof of a negative Coggins test dated within the past 12 months before being gathered together from more than one owner at boarding, breeding, or training stables or pastures.

The age threshold of 6 months is an important detail. Foals under 6 months of age are generally exempt from the testing requirement, but once they reach that age, the standard rules apply. If you keep Tennessee-based equines of any breed — from the fastest horse breeds to working mules — the Coggins requirement covers them all once they pass the 6-month mark.

When a Coggins Test Is Required in Tennessee

Tennessee law is clear about the situations that trigger a mandatory Coggins test. State law requires an annual Coggins test to check for the presence of EIA before any horse is transported from its home farm to a different location. This is the broadest trigger — it applies every time a horse leaves the property where it lives.

Beyond basic transport, the requirement also applies in the following situations:

• Boarding, breeding, or training stables: Every horse or member of the equine family over the age of 6 months must have proof of a negative Coggins test dated within the previous 12 months before being gathered together from multiple owners at boarding, breeding, or training stables or pastures.
• Shows, fairs, and exhibitions: Event officials are required to review official test papers for all equines entered to confirm negative status.
• Sales and change of ownership: A valid Coggins certificate (VS Form 10-11) is needed for buying and selling horses.
• Interstate movement: A current negative Coggins is required when moving a horse into or out of Tennessee.

In general, Coggins papers are valid for up to one year; however, some states or shows may require a negative Coggins test within six months of the event or transportation. Always check the specific requirements of the destination state or event organizer before you load up the trailer.

Pro Tip: Schedule your horse’s annual Coggins test at the same time each year — ideally before peak show or trail-riding season — so you are never caught without current paperwork when you need it most.

How the Coggins Test Works and Approved Testing Methods in Tennessee

The test must be performed by a licensed, accredited veterinarian. Your veterinarian will draw a blood sample from your horse, which will be sent to an accredited lab for analysis along with the EIA form and digital images. The lab will either send your horse’s test results directly to you or your veterinarian once testing is complete.

Two USDA-approved laboratory methods are used to screen for EIA:

• AGID (Agar Gel Immunodiffusion): Also known as the Coggins test, AGID is the most widely accepted procedure for the diagnosis of EIA. The test detects antibody against the viral p26 antigen (major core protein) and is the only procedure statistically correlated with the presence of EIA virus in blood. Results typically take 24–48 hours.
• ELISA (Enzyme-Linked Immunosorbent Assay): ELISA is faster but requires AGID confirmation if a result comes back positive. ELISA tests are more sensitive than AGID but may occasionally yield false-positive results.

Horses or other equines found positive to the official agar gel immunodiffusion test for equine infectious anemia (EIA-AGID) are subjected to a confirmatory retest by a regulatory veterinarian. This two-step process protects horse owners from acting on a false positive.

Tennessee participates in digital Coggins testing. Starting April 15, 2020, all veterinarians and laboratories must use USDA-approved EIA test forms. GlobalVetLink’s digital EIA certificates include the statement “Official EIA Test Form, Approved by USDA Veterinary Services March 2020, GVL” and meet all current federal requirements. Digital certificates allow you to access and share your horse’s test results online through platforms like GlobalVetLink.

Health certificate forms and Coggins test forms are only issued to accredited veterinarians. Contact the Tennessee Department of Agriculture Animal Health office at (615) 837-5120 to order.

Interstate Movement and Import Requirements in Tennessee

Proof of a negative EIA test performed at an accredited laboratory is required for entry into all 50 states. When moving horses into Tennessee from another state, you must carry a current negative Coggins alongside a Certificate of Veterinary Inspection (CVI).

Traveling with horses often requires an up-to-date Certificate of Veterinary Inspection (CVI / health certificate), sometimes current within the last month. In most cases, a CVI is valid for 30 days after the date of issue. This is separate from the Coggins certificate itself, which carries a 12-month validity window in Tennessee.

Tennessee participates in the Extended Equine Certificate of Veterinary Inspection (EECVI) program, which offers a more flexible travel option. EECVIs allow veterinarians and horse owners to obtain a six-month equine health certificate, as long as a current EIA/Coggins test has been provided. An EECVI is valid for six months from the CVI inspection date or until the horse’s current EIA/Coggins test expires, whichever comes first. Since EIA tests are typically valid for 12 months from the blood draw date, the EECVI expiration is determined by whichever date occurs sooner.

A Health Declaration and Movement Permit (HDMP) is the travel document that horse owners create for each individual trip when using an EECVI. Prior to each movement, owners log in to their MyVetLink account, enter their travel dates, origin, destination, and confirm that their horse is healthy. The system generates an HDMP that serves as the documentation displayed when crossing state borders.

Important Note: Requirements vary by destination state. Some states require a Coggins test within six months rather than twelve. Always verify the importing state’s rules with the Tennessee Department of Agriculture Animal Health office or the destination state’s animal health authority before you travel.

For horses being imported from outside the United States, the USDA requires all imported horses from foreign countries to have a negative AGID EIAV test. Animals exported outside the United States are subject to federal regulations. Contact USDA Veterinary Services for more information at (615) 781-5310.

What Happens When a Horse Tests Positive in Tennessee

A positive result sets a regulated process in motion immediately. A positive result triggers a strict regulatory process. The horse must be placed under quarantine within 24 hours while a confirmatory AGID test is run. All horses within 200 yards of the positive animal are also quarantined, since biting flies can easily cover that distance.

Within 24 hours of a positive result, your horse will be placed in quarantine more than 200 yards from other horses until confirmation testing and classification is complete. The state vet will be informed and a case will be opened to ensure proper protocols are followed.

EIA is a reportable animal disease in all states. Positive results must be reported to state and federal animal health authorities. In Tennessee, the Tennessee Department of Agriculture coordinates the response alongside USDA Veterinary Services.

Once the confirmatory AGID test confirms the positive result, the horse is officially classified as a “reactor.” At that point, the owner faces three options: euthanasia, slaughter at a federally inspected facility, or permanent lifetime quarantine at the premises of origin. The horse can never attend shows, trail rides, or any gathering of horses again.

Confirmed reactors must also be permanently marked. Confirmed reactors must be permanently marked. A state-assigned code number followed by the letter “A” is applied to the left shoulder or left side of the neck using a hot iron, chemical brand, or freeze mark, with characters at least two inches high. Alternatively, a lip tattoo with characters at least one inch high can be placed on the inside of the upper lip. This marking ensures the horse is identifiable as EIA-positive for life.

Foals nursing reactor mares are considered quarantined with their dams. Weaned foals may be released if they test negative to the EIA-AGID test after a 90-day period of isolation from their dam and other horses.

Quarantine, Euthanasia, and Isolation Rules in Tennessee

The 200-yard quarantine distance is not arbitrary. Flies cannot travel very far, and the virus does not persist on their mouthparts very long, which is why an EIA-positive horse can be kept in quarantine as long as they remain 200 yards (600 feet, 183 meters) from uninfected horses. The most common insects known to transmit EIA virus are horseflies and deerflies, but stable flies can also be responsible for viral spread.

The three permanent disposition options for a confirmed reactor in Tennessee are:

1. Euthanasia: Humane euthanasia performed by a licensed veterinarian. Due to the limited availability of quarantine facilities and the decrease in quality of life due to being isolated from the herd, most owners elect euthanasia if their horse tests positive.
2. Permanent lifetime quarantine: The horse must remain at least 200 yards from all other horses for the rest of its life, and regulatory officials will periodically inspect the quarantine to verify compliance.
3. Research facility placement: Horses may also be sent to a research facility if neither of the previous options is suitable.

If the horse is not going to be euthanized, it must be branded on the lip or the left shoulder. Special permits must be obtained to move the horse from the quarantine area.

Horses that were exposed to the positive animal but have not yet tested positive face their own quarantine period. Exposed horses will not be released from quarantine until they are retested negative at least 60 days after isolation or the positive horse is removed from the premises.

Under Tennessee’s official rules, horses or other equines found positive to the official AGID test for EIA are subjected to a confirmatory retest by a regulatory veterinarian, and all equines associated with that animal on the premises — farm, pasture, or stable — are officially tested.

Important Note: If you have questions about quarantine procedures or need to report a suspected EIA case, contact the Tennessee Department of Agriculture Animal Health office at (615) 837-5120 or email animal.health@tn.gov.

Penalties for Non-Compliance in Tennessee

Failing to comply with Tennessee’s Coggins test requirements carries real legal and financial consequences. Tennessee’s animal health statutes — codified under Tenn. Code Ann. §§ 4-3-203 and 44-2-1302 — grant the state authority to enforce EIA regulations, including the power to quarantine premises and impose penalties on non-compliant owners.

Practical consequences of non-compliance include:

• Denial of entry to events: Officials at most every event or show will ask to see a copy of your horse’s current negative Coggins test and/or a certificate of veterinary inspection (CVI). Without current paperwork, your horse will be turned away.
• Forced quarantine of your entire herd: If a horse on your property is found to lack a current Coggins test and later tests positive, all equines on the premises face quarantine and mandatory testing at your expense.
• Civil penalties: Tennessee’s Department of Agriculture has authority to issue civil fines for violations of animal health regulations, including failure to maintain required testing records.
• Loss of the animal: A horse transported without a current Coggins that is subsequently found positive will be subject to the same reactor disposition rules — euthanasia, quarantine, or research facility placement — with no exceptions.

Cases must be reported to state and federal animal health authorities. Owners who attempt to conceal a positive result or move a known reactor without authorization face additional regulatory action under both state and federal law.

The best way to avoid any penalty is straightforward: state law requires a yearly Coggins test to check for the presence of EIA before any horse is transported from its home farm to a different location, and horse owners should consult with their veterinarian to establish a regular testing schedule.

Staying compliant also protects the broader Tennessee equine community. Thanks to routine testing and responsible horse ownership, EIA is now rare, but continued vigilance is essential. If you own other animals in Tennessee and want to stay informed about additional state regulations, you may also find it useful to review rabies vaccine requirements in Tennessee or explore fishing license requirements in Tennessee for a broader picture of the state’s animal-related rules.

For the most current Tennessee-specific requirements, contact the Tennessee Department of Agriculture Animal Health division directly at (615) 837-5120 or visit the C.E. Kord Animal Health Diagnostic Laboratory, which handles official EIA testing for the state. Requirements can change, and your accredited veterinarian is your most reliable resource for staying current with both state and federal rules.