Coggins Test and EIA Requirements in Mississippi: What Every Horse Owner Must Know
July 23, 2026
If you own, transport, sell, or compete with horses in Mississippi, a negative Coggins test is not optional — it is the law. Equine Infectious Anemia (EIA) is a transmissible infectious disease of horses caused by an RNA virus in the Lentivirus genus, family Retroviridae. Mississippi has some of the broadest EIA testing mandates in the country, applying to virtually every equine movement and public activity in the state.
Understanding exactly which animals need testing, when the test must be done, and what happens if a horse tests positive can protect you from serious legal consequences — and protect your herd from a disease that has no cure. This guide walks through every layer of Mississippi’s EIA and Coggins test requirements so you can stay fully compliant.
What Is Equine Infectious Anemia (EIA) and Why It Is Regulated in Mississippi
Equine Infectious Anemia is a viral, and sometimes fatal, disease that only affects equids — horses, ponies, zebras, mules, and donkeys. There is no vaccine or treatment for the disease, and infection often results in a lifelong carrier state if the horse survives the acute phase.
In nature, the equine infectious anemia virus (EIAV) is a vector-transmitted disease. Blood-feeding insects transfer virus-infective blood between horses, and horse flies, deer flies, and stable flies are the most common vectors. EIAV can also be transmitted unintentionally by mechanical means, such as transfusion of infective blood or blood-contaminated instruments.
Some horses infected with EIAV never exhibit noticeable symptoms but are lifelong inapparent carriers and a reservoir for the virus. For most EIA-infected horses, the frequency of recurrent episodes and severity of clinical symptoms subside within one year of initial infection, and these horses also become inapparent carriers. That silent carrier status is precisely why regulation is so strict.
Mississippi has historically ranked among the higher-incidence states for EIA. EIA is a reportable disease regulated by the United States Department of Agriculture (USDA) and state animal health regulatory agencies. Efforts to control EIA in the United States started in 1972, and since then the estimated national prevalence has dropped from nearly 4 percent in 1972 to 0.004 percent. Mississippi’s mandatory testing rules have played a direct role in that long-term decline.
Key Insight: EIA is sometimes called “swamp fever” because it has historically been associated with warm, wet regions — conditions that describe much of Mississippi. The state’s climate makes robust testing requirements especially important for protecting local horse populations.
Which Animals Require a Coggins Test in Mississippi
EIA is a viral disease affecting only members of the equidae family — horses, ponies, zebras, mules, and donkeys. Mississippi’s regulations apply to all of these animals, with one narrow exception.
All equidae, except nursing foals, located on any premises within the state where the public participates in equine activities for any purpose — including, but not limited to, training, breeding, performing, or exhibition — must be accompanied by the original copy of a negative current EIA test. All equidae moving within the state for any reason must be accompanied by the original copy of a negative valid EIA test, and equidae being sold at a public sale or private sale must also have a negative valid EIA test.
The table below summarizes which animals fall under the testing requirement and which are exempt:
| Animal Type | Testing Required? | Notes |
|---|---|---|
| Horses (all ages, except nursing foals) | Yes | Required for movement, events, and sales |
| Mules | Yes | Covered under “equidae” definition |
| Donkeys / Jacks / Burros | Yes | Covered under “equidae” definition |
| Ponies | Yes | Covered under “equidae” definition |
| Nursing foals | No | Explicitly exempt under state regulation |
If you are unsure whether your animal qualifies as a nursing foal under state guidelines, contact the Mississippi Board of Animal Health directly for clarification before transport or sale.
When a Coggins Test Is Required in Mississippi
Mississippi’s testing triggers are broad and cover nearly every scenario in which an equine changes location or is exposed to the public. You need a valid, negative EIA test on hand in each of the following situations:
- Any intrastate movement: All equidae moving within the state for any reason must be accompanied by the original copy of a negative valid EIA test.
- Public equine activities: All equidae, except nursing foals, located on any premises within the state where the public participates in equine activities — including training, breeding, performing, or exhibition — must be accompanied by the original copy of a negative current EIA test.
- Sales (public and private): Equidae being sold at a public sale or private sale must have a negative valid EIA test.
A valid EIA test is one that is negative, has been performed at a laboratory approved by the State Veterinarian, and issued by a licensed, accredited veterinarian within the past 12 months. Keep the original test certificate — not a copy — with the animal at all times during transport or when at a public facility.
A horse or other equidae receiving a premises test may not be sold or have title otherwise transferred until the results of the EIA test are returned. Plan testing well in advance of any planned sale to avoid delays.
Pro Tip: Mississippi participates in the Extended Equine Certificate of Veterinary Inspection (EECVI) program. 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, the EECVI expiration is determined by whichever date occurs sooner. This can reduce paperwork costs for horse owners who travel frequently.
How the Coggins Test Works and Approved Testing Methods in Mississippi
The Coggins test is named after Dr. Leroy Coggins, who developed it in the 1970s. It is a blood test that determines whether a horse is carrying EIA, a viral and deadly disease among equines. Definitive diagnosis of EIA is made by identifying antibodies in a blood sample, and two types of diagnostic tests are approved by the USDA for diagnosis of EIAV: the agar gel immunodiffusion (AGID) test and several enzyme-linked immunosorbent assay (ELISA) tests.
The AGID test, commonly known as the Coggins test, is the most widely used tool for diagnosing EIA. It is highly specific and 95 percent accurate but may yield an occasional false-negative result. ELISA tests are popular for their simplicity and rapid results, and are more sensitive than the AGID, but may occasionally yield false-positive results.
All ELISA-positive tests must be confirmed with an AGID test, and when used together, the Coggins and ELISA tests provide the highest level of accuracy. The Western blot test is a specialized diagnostic tool that may be used to clarify conflicting results.
For the test to be valid in Mississippi, the following procedural requirements must be met:
- Horses or other equidae to be tested must be completely and properly identified by licensed, graduate veterinarians using the official test forms provided by the office of the State Veterinarian.
- Only one chart per horse may be used. If the animal is registered, its registration number must be entered on the chart. Any distinctive markings — brands, tattoos, stars, snips, stockings, or other markings — must also be noted on the official chart.
- Any EIA test on equine located in Mississippi must be reported on official forms furnished by the office of the State Veterinarian.
- The test must be conducted at an approved laboratory, and the name of the laboratory and the case number must appear on the test chart.
Accredited veterinarians must complete a VS Form 10-11 either electronically or by paper using one of the USDA-approved systems or forms, and submit samples to APHIS-approved labs. Starting April 15, 2020, all veterinarians and laboratories must use USDA-approved EIA test forms.
Interstate Movement and Import Requirements in Mississippi
Moving a horse into Mississippi from another state carries its own set of documentation requirements that go beyond just the Coggins test. Proof of a negative EIA test performed at an accredited laboratory is required for entry into all 50 states.
For horses entering Mississippi specifically, an official Certificate of Veterinary Inspection (OCVI) issued by a licensed accredited veterinarian, or state or federal veterinarian, is required, showing the name, breed, registration number (if any), tattoo or brand (if any), sex, age, color, and markings of each horse listed on the certificate. The name of the laboratory, laboratory number, date of test, and test results for each horse must also be recorded on the health certificate.
A record of physical examination of each animal, verifying the animal to be free of symptoms of any infectious, contagious, or communicable disease, must also be included. An official copy of the Coggins test, certifying the animal to be negative within the past 12 months, must accompany the health certificate.
Mississippi also participates in the EECVI program, which can simplify repeated interstate travel. As of May 2023, Mississippi is among the states participating in the EECVI program. If you use an EECVI for travel into or out of Mississippi, the Health Declaration and Movement Permit (HDMP) must be kept together with the EIA/Coggins test — digital or paper copies are acceptable — for the EECVI to remain valid.
If you regularly transport horses across state lines for shows or events, review the livestock trailer requirements in Mississippi to make sure your hauling setup also meets state standards.
Important Note: State entry requirements can change. Always verify current import rules directly with the Mississippi Board of Animal Health before crossing state lines, especially for horses entering from states with recent disease activity.
What Happens When a Horse Tests Positive in Mississippi
A positive EIA result triggers an immediate and structured regulatory response. Positive test results automatically result in the quarantine of the animal without further notice at the premises of the owner or where the test was conducted.
Horses or other equidae found positive to an official test for EIA must have a confirmatory retest by state regulatory personnel within 15 days of the initial test. This retest is conducted by state officials — not the owner’s private veterinarian — to ensure independent verification.
Animals positive on the retest must be freeze branded on the left side of the neck or left shoulder, at the discretion of the state equine inspector, with the characters “65-A” and the official reactor number assigned by the Veterinary Diagnostic Laboratory. The owner must submit the animal for branding by regulatory personnel within 15 days of the confirmatory test.
Once branded, the owner faces a choice about the animal’s disposition. Any horse or other equidae found to be infected with EIA must be isolated or sold for slaughter within seven days of branding. Positive animals are subject to the following disposition, at the option of the owner: with approval of the State Veterinarian or his designated inspector, the animal may be sold for slaughter to bona fide slaughter buyers.
No person may change, alter, or forge the names, dates, description, signature, or other information on an official certificate of veterinary inspection or EIA test chart. Altering official documents is a separate violation that carries additional consequences.
Quarantine, Euthanasia, and Isolation Rules in Mississippi
If the owner chooses not to sell the reactor for slaughter, strict quarantine is the alternative. EIA reactors must be permitted on Form 1-27 provided by the inspector for movement from farm to sale and/or from sale to slaughter establishment, or quarantined in an isolation facility on the owner’s premises or elsewhere, with that facility approved by an authorized representative of the Board of Animal Health. A written quarantine is issued for each case.
Minimum standards for an approved isolation facility require a plot or pasture located a minimum of 200 yards from any other horse enclosure, horse, or other equidae (except another known EIA reactor). This distance requirement reflects how EIA spreads through biting insects — keeping reactors far from other horses reduces the chance that a fly feeding on an infected animal will then bite a healthy one.
Infected animals that survive the disease become virus carriers and can infect other equids for life. They must either be euthanized or permanently isolated from other equids to prevent transmission. Carriers may also experience clinical flare-ups, often following stress or strenuous work.
The table below outlines the disposition options available to owners of confirmed EIA reactors in Mississippi:
| Disposition Option | Requirements | Approval Needed |
|---|---|---|
| Sale for slaughter | Must use bona fide slaughter buyers; Form 1-27 required for movement | State Veterinarian or designated inspector |
| Permanent quarantine on premises | Isolation facility at least 200 yards from all other equidae | Mississippi Board of Animal Health representative |
| Euthanasia | Humane destruction; eliminates ongoing transmission risk | Coordinated with state regulatory personnel |
The USDA and state animal health regulatory agencies require euthanasia or strict lifelong quarantine for horses testing positive for EIA. Euthanasia, while difficult, removes the transmission risk entirely and is often the recommended path from a disease-control standpoint.
Penalties for Non-Compliance in Mississippi
Mississippi takes EIA testing compliance seriously, and violations carry real legal consequences. Any person violating Section 69-15-117 or the rules and regulations promulgated under it by the Board of Animal Health is subject to the penalties provided in Section 69-15-65 of the Mississippi Code.
Violations can arise in several ways. Moving an untested horse within the state, presenting an equine at a public event without valid test documentation, selling a horse without a current negative EIA test, or altering an official test chart all constitute non-compliance. No person may change, alter, or forge the names, dates, description, signature, or other information on an official certificate of veterinary inspection or EIA test chart.
Beyond financial penalties, non-compliance can result in:
- Immediate removal of your animals from a sale, event, or public facility
- Mandatory quarantine of your entire herd pending testing
- Referral to the State Veterinarian for further enforcement action
- Loss of access to licensed livestock markets in Mississippi
All tests for EIA by laboratories other than the Veterinary Diagnostic Laboratory of Mississippi must be reported to the Board of Animal Health. Failure to report results from outside laboratories is itself a compliance issue that can draw regulatory scrutiny.
Pro Tip: Keep digital and physical copies of your horse’s current Coggins certificate in multiple locations — your trailer, your phone, and a secure home file. If the original is lost during transport, you may be turned away from events or sales until a replacement is obtained from the issuing veterinarian or laboratory.
Staying current on testing is the simplest way to avoid all of these consequences. Schedule your annual Coggins test well before peak show and sale season so results are in hand before you need them. For more information on Mississippi’s equine and animal regulations, explore related resources on wildlife in Mississippi or review native species guides that cover the broader animal landscape of the state.
For the most current regulations and approved laboratory listings, contact the Mississippi Board of Animal Health, Chapter 10 equine regulations directly, or consult a licensed, accredited veterinarian in your area before any planned movement, event, or sale.