EIA and Coggins Test Requirements in Michigan: What Every Horse Owner Must Know

If you own a horse in Michigan, a negative Coggins test is not optional — it is the law. Whether you plan to show your horse, sell it, move it to a new location, or bring one in from another state, Michigan’s equine infectious anemia regulations apply to you directly. Failing to comply can result in quarantine, civil penalties, or worse.

This guide covers every aspect of Michigan’s EIA and Coggins test requirements, from which animals must be tested and when, to what happens if your horse comes back positive. Understanding these rules protects your horses, your neighbors’ horses, and the broader equine industry across the state.

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

Equine Infectious Anemia (EIA), also known as Coggins Disease, is a disease caused by a virus that produces anemia, intermittent fever, and severe weight loss. Equidae — horses, ponies, mules, and donkeys — are the only animals known to be affected by the virus. The equine infectious anemia virus (Equine infectious anemia virus, or EIAV) belongs to the lentivirus family and attacks white blood cells, triggering immune-mediated destruction of red blood cells and potential damage to vital organs including the liver, heart, and kidneys.

Once an animal is infected with the virus, it is infected for life regardless of the severity of the symptoms. No treatment is effective against the EIA virus. Although most infected horses show no symptoms, they remain contagious for life, endangering the health of other horses.

The disease is also known as “Swamp Fever” because insects that transmit the virus — horse flies and deer flies — thrive in hot, humid conditions. Transmission may also occur when blood-contaminated objects such as needles, syringes, or surgical instruments are used on more than one animal. EIA can also be transmitted through the semen of an infected stallion, and foals can be infected before birth.

Michigan lies outside the so-called “hot zone” for EIA, which spans the southern United States and states bordering the Mississippi River. Because of this, Michigan’s equidae are at the highest risk of becoming infected when they commingle with horses that come from hot-zone states — whether Michigan horses travel out of state or horses from hot-zone states travel to Michigan. This cross-state movement risk is precisely why Michigan law mandates testing at key points of movement and sale.

Key Insight: EIA is a reportable disease in Michigan. If you suspect a horse has EIA, contact MDARD immediately at 800-292-3939 (daytime) or 517-373-0440 (after-hours), or submit a Reporting a Reportable Animal Disease (RRAD) Form to mireportableanimal@michigan.gov.

Which Animals Require a Coggins Test in Michigan

Equine infectious anemia is a viral disease that afflicts members of the family Equidae, including horses, ponies, mules, donkeys, burros, and zebras. All of these animals fall under Michigan’s EIA testing statute, not just horses in the traditional sense.

Tests are not required for animals six months old or younger and nursing. Nursing foals under six months of age that are accompanied by an EIA-negative dam do not need an EIA test. However, if the dam will not accompany the foal, a negative EIA test is required. This exception is narrow — the moment a young foal is separated from its dam for movement or sale purposes, the testing requirement kicks in.

Beyond the nursing foal exception, horses six months or older must have an EIA test, also known as a Coggins test, with a negative result completed within the past 12 months whenever they enter one of the regulated situations described below. The requirement applies equally to horses already in Michigan and to those being imported from other states.

Animal Type	Testing Required?	Exception
Horses, ponies, mules, donkeys (6+ months)	Yes	None
Burros and zebras (6+ months)	Yes	None
Nursing foals (under 6 months) with EIA-negative dam	No	Dam must accompany foal
Nursing foals (under 6 months) without dam	Yes	No exception applies

When a Coggins Test Is Required in Michigan

Michigan law specifies several distinct situations that trigger the Coggins test requirement. You need to know all of them, because missing any one of them puts you in violation of the Michigan Animal Industry Act (MCL 287.717c).

Equids moving within the state of Michigan for public events, livestock markets, or sale with change of location must have proof — an official USDA test chart or equivalent — of a negative EIA test done within 12 months prior to movement. The four primary triggering events are:

• Exhibitions, fairs, and shows: Michigan equidae owners must have an official EIA test with negative results within the past 12 months if equidae are entered into fairs, shows, exhibitions, or similar events.
• Horse auctions and sale markets: Any equid entering, remaining at, or present on the premises of horse auctions or sales markets — whether or not licensed — requires a current negative test. If an EIA test is not possible before sale, the equid must be held on the sale premises until the test results are known.
• Change of ownership and location: An equid that changes ownership and location in this state must have an official EIA test with a negative result within the previous 12 months.
• Interstate movement into Michigan: An equid moved into this state from another state must meet the requirements of section 19 of the Animal Industry Act, which includes a negative EIA test within 12 months as part of the Certificate of Veterinary Inspection (CVI).

Persons transporting equidae within Michigan using public streets, roads, and highways do NOT need proof of annual EIA testing simply to be on the road. Routine trail rides or transport between your own properties on public roads do not independently trigger the requirement, provided no sale, show, or location-change event is involved.

Pro Tip: Show authorities are required to confirm proof of negative test status for all entered animals. Arrive at any Michigan equine event with your official test documentation in hand — show management can and will turn you away without it.

How the Coggins Test Works and Approved Testing Methods in Michigan

The Coggins test is a blood-based diagnostic tool that detects antibodies against the EIA virus in equine serum. A Coggins test is a blood test that determines whether a horse is carrying EIA, which is a viral and deadly disease among equines. Two laboratory methods are currently accepted for official EIA testing in the United States and Michigan.

The original and still-standard method is the Agar Gel Immunodiffusion (AGID) test — commonly called the Coggins test after its developer, Dr. Leroy Coggins. The AGID test detects antibodies from equine blood against the EIA virus. It is extremely likely that an animal that tests positive on one occasion will do so for the rest of its life. The second approved method is the competitive ELISA (cELISA). ELISA tests require only a few hours to complete, while positive ELISA tests are confirmed by running the Coggins (AGID) test. The cELISA test is accepted for movement throughout the U.S. and Canada.

The MDARD Animal Disease Testing Laboratory charges $8.00 for an EIA Coggins test (AGID or ELISA). Samples must be submitted using USDA-compliant forms. Effective immediately, MDARD only accepts EIA submissions that are in compliance with the USDA requirements for testing that went into effect April 15, 2020. Non-compliant samples will not be tested and will be discarded.

Samples must be submitted by a USDA accredited Category II veterinarian who is authorized to complete accredited duties in the state where the sample is obtained. You cannot collect your own blood sample for official EIA testing — the accredited veterinarian requirement is non-negotiable. All tests require a minimum of 1ml serum, preferably in a serum separator tube and spun before mailing. If whole blood is submitted, it is best to ship the sample chilled with a cold pack to preserve it, especially in the summer months.

An EIA laboratory test form must contain, at a minimum, the color, breed, sex, age, markings, name of owner, and location or address of the equid to which it applies. Digital EIA certificates are also accepted. Starting April 15, 2020, all veterinarians and laboratories must use USDA-approved EIA test forms. GlobalVetLink’s digital EIA certificates meet all current federal requirements.

The MDARD Animal Disease Testing Laboratory is located at 1615 S. Harrison, East Lansing, Michigan 48823. You can also work with GlobalVetLink’s digital EIA testing platform for electronic submission and certificate management.

Interstate Movement and Import Requirements in Michigan

Bringing a horse into Michigan from another state involves both federal and state-level documentation requirements. Getting this wrong can result in the animal being turned back at the border or placed under quarantine upon arrival.

According to the Michigan Department of Agriculture and Rural Development (MDARD), all horses entering Michigan from another state must meet the following requirements:

• Certificate of Veterinary Inspection (CVI): An official interstate CVI is required for all horses entering Michigan.
• Negative EIA test within 12 months: Horses must have a negative EIA test done within 12 months. The date of test, negative result, and laboratory name and accession number must be provided on the interstate CVI.
• Nursing foal exception: Nursing foals under six months of age accompanied by the EIA-negative dam do not need an EIA test. If the dam will not accompany the foal, a negative EIA test is required.
• Quarter Horses entering for racing: Quarter Horses must have a negative equine piroplasmosis (EP) test, specifically c-ELISA for Theileria equi within 12 months, if coming to Michigan for racing, training for racing, or stabling for racing. This does not apply to barrel racing horses. The date of test, negative result, and type of test must be provided on the CVI, and blood samples must be collected by an accredited veterinarian and tested at an approved USDA laboratory.

Important Note: Requirements vary by destination state as well. All 50 states, including Michigan, require a negative Coggins test for entry. Requirements vary from state to state, with some requiring the test drawn in the past 12 months, 6 months, or in the case of Wisconsin, the calendar year. Always contact the destination state’s veterinary authority before traveling out of Michigan with your horse.

The person or entity responsible for moving a horse interstate must ensure they have an ICVI or other USDA-required document. The Michigan Horse Council recommends contacting the state veterinarian’s office for the most current regulations well in advance of any travel. If you are also interested in other Michigan animal regulations, the rabies vaccine requirements in Michigan apply to equines in certain contexts as well.

What Happens When a Horse Tests Positive in Michigan

A positive Coggins test result is a serious, industry-wide event. When a horse receives a positive Coggins test, it is an industry-wide problem. By knowing where positive horses are located, public health officials can prevent the spread of EIA and reduce potential impact to the entire industry. Once positive horses are identified and separated from others, the transmission of EIA ceases.

The moment a positive result is confirmed, a mandatory reporting chain begins. EIA is a reportable disease and must be reported to all relevant authorities such as state veterinarians and federal animal health entities. If a horse tests positive for equine infectious anemia, owners are required to quarantine every horse on their property within the first twenty-four hours after infection is confirmed. An APHIS-certified veterinarian will then come and test all exposed horses on the property to determine how many have EIA.

Michigan law under MCL 287.717c sets out specific obligations for the owner of a test-positive equid. To the best of their knowledge, the owner of an EIA test-positive equid must provide to MDARD records reflecting the time period during which the test-positive equid had been on the premises and had been a member of the equid herd. The owner cannot destroy an official EIA test-positive equid without permission from the director. The director must be present when the equid is destroyed, or must allow an accredited veterinarian to document and certify that the test-positive equid has been destroyed.

The positive result also triggers an epidemiological investigation. Michigan law requires the owner to provide MDARD with detailed records about the equid’s herd history and movements. When MDARD announced a positive Coggins test in Mecosta County — the first positive horse in Michigan since 2008 — the 17-year-old grade mare was euthanized as a result of the diagnosis. This real-world example illustrates how swiftly the protocol moves once a positive result is confirmed.

Quarantine, Euthanasia, and Isolation Rules in Michigan

Michigan’s Animal Industry Act provides a detailed framework for what must happen to a test-positive equid and the herd it came from. The options for the owner are extremely limited, and the state retains significant authority over the outcome.

If your horse tests positive for EIAV, your options are extremely limited. Federal and state health agencies, as well as the American Association of Equine Practitioners, support euthanasia as the most prudent option. Under Michigan law, the two permitted outcomes for a confirmed positive equid are euthanasia or permanent, strictly regulated quarantine.

If quarantine is chosen instead of euthanasia:

• An EIA test-positive equid that is moved to a permitted quarantine location shall remain quarantined under state authority at that location until natural death, slaughter, or euthanasia.
• Positive horses must be kept 200 yards away from all other equids, since this is the distance a horsefly can travel and still transmit the live EIA virus.
• Owners who choose quarantine must post signs clearly stating: “Quarantined: Equine Infectious Anemia” or “Swamp Fever.”
• A person cannot destroy or remove an official EIA test-positive equid from the original test location or premises without prior permission from the director.

For the source herd — meaning all horses that shared the same premises as the positive equid — Michigan law establishes a seasonal testing schedule before quarantine can be released:

• Between November 1 and April 30, a source herd may be tested at any time and qualify for quarantine release if all tested equids are negative to an official EIA test.
• Between May 1 and October 31, a source herd may be tested after waiting a minimum of 45 days after the test-positive equid has been removed or segregated from the herd. If all equids tested are negative to the official EIA test, the quarantine may be released.

An individual exposed equid may be allowed to move from a quarantined area for specific purposes if it has a negative test at the time of movement. The equid must be moved under quarantine and maintained under quarantine at the new premises until tested negative to an official EIA test at least 60 days after movement.

If you own horses in Michigan, learning more about disease reporting obligations is essential. The Michigan reportable livestock disease rules outline who must report, which diseases qualify, and the timelines required under state law. You may also find it useful to review rabies vaccine requirements for cats in Michigan if you keep multiple species on your property.

Penalties for Non-Compliance in Michigan

Michigan’s Animal Industry Act treats EIA testing violations seriously. Penalties range from civil fines to criminal charges depending on the nature and severity of the violation, and the state has broad enforcement authority.

The enforcement framework under Section 287.744 of the Animal Industry Act covers both criminal and civil liability. Violations of the act or its rules can be prosecuted as misdemeanors, and more serious offenses — such as knowingly moving a quarantined animal — can rise to felony-level charges. The state can also pursue civil penalties and recover costs and attorney fees in enforcement actions.

A person that knowingly possesses or harbors affected or suspected animals shall not expose other animals to the affected or suspected animals or otherwise move the affected or suspected animals or animals under quarantine except with permission from the director. Violating a quarantine order is one of the most serious offenses under the act.

The director may call upon a law enforcement agency to assist in enforcing the director’s quarantines, orders, or any other provision of the act. This means local law enforcement can become directly involved in EIA compliance situations — it is not purely a regulatory matter handled only by MDARD.

Beyond the legal consequences, consider the practical ones. Moving an untested horse to a show or sale and having it test positive on-site results in immediate quarantine of all exposed animals at that venue — affecting every other horse owner present. The financial and reputational damage from such a scenario extends well beyond any fine MDARD might assess.

Important Note: If you are buying or selling a horse in Michigan, confirm that the EIA test documentation accompanies the animal before the transaction is finalized. A test-positive horse discovered post-sale creates complex legal and regulatory obligations for both parties under Michigan law.

Staying current with your horse’s Coggins test is one of the simplest and most cost-effective things you can do as a Michigan equine owner. Testing is the only way to maintain an “EIA free” herd, whether referring to personal horses or the entire state. Schedule your annual test with an MDARD-accredited veterinarian well before show season or any planned sale — and keep that documentation with your horse at all times.

If you enjoy learning about Michigan’s animal regulations and wildlife, explore our guides on hummingbirds in Michigan, types of hawks in Michigan, and the fastest horse breeds for more reading on equines and Michigan’s diverse animal life. You can also check out the fishing license requirements in Michigan if you hold other outdoor activity licenses in the state.