What Vaccines Does USEF Require for Horse Shows?

By Dr Duncan Houston

Rule status checked: July 20, 2026

Arriving at a United States Equestrian Federation competition with a vaccinated horse is not necessarily the same as arriving with a USEF-compliant horse.

The vaccines must cover the correct diseases, fall within the correct time window and be supported by acceptable documentation. If the paperwork does not meet the rule, competition management may require the horse to leave the grounds, even if the owner is confident that the vaccinations were given.

Under the current USEF Equine Vaccination Requirement, identified as GR845, horses more than seven months old must have documented equine influenza and equine herpesvirus vaccinations within the six months before entering the competition stables. (USEF)

Quick Answer

Horses more than seven months old entering a USEF-licensed competition must be accompanied by documentation showing vaccination against:

• Equine influenza virus, or EIV

• Equine herpesvirus, or EHV, commonly called rhinopneumonitis

Both vaccinations must have been administered within the six months before the horse enters the stables. Horses that do not comply may be required to leave the competition grounds.

Veterinarian-administered vaccines require veterinary documentation showing the vaccine names and administration dates. Vaccines administered by an owner or agent require more detailed proof, including a signed purchase receipt, vaccine name, serial number, expiration date and administration date. A medical exemption requires a veterinary letter and twice-daily temperature records. (USEF)

What Exactly Does USEF Rule GR845 Require?

Requirement	Current USEF rule
Which horses are covered?	Horses more than seven months of age entering the competition grounds
Which vaccines are required?	Equine influenza virus and equine herpesvirus, or rhinopneumonitis
How recent must they be?	Administered within six months before entering the stables
When must proof be available?	When requested by competition management
What can happen if the horse is not compliant?	The horse may be required to leave the competition grounds
Current rule reference	USEF GR845

The requirement applies when the horse enters the competition environment. It is not calculated from the time of the horse’s first class, the closing date for entries or the day the competition officially begins. (USEF)

Are Influenza and EHV Core Horse Vaccines?

Not under the American Association of Equine Practitioners classification.

The AAEP identifies the following as core vaccines for horses in the United States:

• Tetanus

• Eastern and Western equine encephalomyelitis

• West Nile virus

• Rabies

Equine influenza and equine herpesvirus are classified as risk-based vaccines. However, they become mandatory for horses entering USEF competition grounds because travelling, stabling and mixing with unfamiliar horses create a substantial respiratory disease risk. (AAEP)

This distinction matters. A horse can be fully compliant with USEF’s influenza and EHV rule while still being overdue for tetanus, rabies, West Nile virus or encephalomyelitis vaccination.

USEF compliance should therefore be treated as one part of the horse’s vaccination program, not as proof that every recommended vaccine is current.

Why Does USEF Require Influenza and EHV Vaccination?

Competition grounds bring horses from multiple farms, states and sometimes countries into close proximity. Horses may share airspace, wash areas, handling staff, trailers and equipment.

Equine Influenza

Equine influenza is a highly contagious respiratory infection. Common signs include:

• Fever

• Dry or persistent coughing

• Nasal discharge

• Lethargy

• Reduced appetite

• Enlarged lymph nodes

The virus can spread through respiratory droplets and contaminated hands, clothing, buckets, tack, trailers and other equipment. Vaccinated horses can still become infected, but appropriate vaccination may reduce disease severity and the amount of disruption caused by an outbreak. (AAEP)

Equine Herpesvirus

EHV-1 and EHV-4 commonly cause respiratory disease, including fever, lethargy, reduced appetite, nasal discharge and coughing.

EHV-1 can also cause:

• Abortion

• Fatal disease in newborn foals

• Neurological disease known as equine herpesvirus myeloencephalopathy, or EHM

Young horses, stressed horses and horses from different sources that are brought together are particularly vulnerable to respiratory EHV transmission. (AAEP)

Does the EHV Vaccine Prevent Neurological EHV?

No current vaccine is labelled to prevent the neurological form of EHV-1, known as EHM.

EHV vaccination may reduce respiratory disease, clinical severity and viral shedding, which can help reduce transmission. It does not guarantee that a vaccinated horse cannot become infected or develop neurological disease. (USEF)

This is one of the most important points for competitors to understand:

An EHV vaccination certificate is not an invisible force field against EHM.

Temperature monitoring, early isolation, careful hygiene and prompt reporting of sick horses remain essential.

Which Horses Must Comply?

GR845 applies to horses more than seven months old entering USEF competition grounds.

The wording is broader than simply “horses entered in a class.” A horse brought onto the grounds as a companion, sales horse, demonstration horse or non-competing stablemate may still fall within the rule’s wording.

When the horse’s circumstances are unusual, contact competition management before travelling rather than attempting a legal interpretation from the trailer ramp.

What About a Foal Seven Months Old or Younger?

A horse that is not yet more than seven months old is outside the specific age threshold stated in GR845.

That does not mean the foal should be unvaccinated or can automatically enter every event. The foal may still be subject to:

• Venue-specific health requirements

• State movement regulations

• Outbreak controls

• A veterinarian-designed primary vaccination schedule

• Additional breed or discipline rules

Foal vaccination schedules also differ from adult booster programs because maternal antibodies can affect the response to early vaccination.

How Do You Calculate the Six-Month Window?

Count backwards from the date the horse will enter the competition stables.

Do not calculate from:

• The date of the horse’s first class

• The final day of the competition

• The entry closing date

• The date the trailer leaves your home farm

• The vague statement that the horse is vaccinated “twice a year”

For example, if the horse will enter the stables on October 20, a vaccination dated April 20 sits directly on the six-month boundary. Do not build an expensive competition trip around a borderline date. Arrange the booster earlier or obtain written confirmation from competition management before travelling.

“Twice a Year” Does Not Automatically Mean Compliant

A horse may receive two boosters during a calendar year and still fall outside the six-month window for a particular competition.

The actual administration date matters. January and July vaccinations do not automatically cover every possible arrival date, especially if a booster is delayed or the show schedule changes.

A practical competition program may therefore use slightly shorter intervals so that every planned arrival remains comfortably inside the rule.

How Close to a Competition Should the Horse Be Vaccinated?

GR845 establishes a maximum look-back period. It does not mean that the ideal time to vaccinate is the afternoon before loading the trailer.

Protection is not immediate. The AAEP advises that primary vaccination series and booster doses should generally be completed at least 14 days before likely exposure. This gives the immune system time to respond and also allows time for unexpected soreness, fever or lethargy to resolve before transport and competition. (AAEP)

For most competition horses, a sensible approach is to administer a required booster approximately two to four weeks before travel, provided this fits the veterinarian’s plan and the product instructions.

Vaccinating at the last minute creates several avoidable problems:

• The horse may not have developed useful immunity

• A mild vaccine reaction may interfere with performance

• Fever following vaccination may be difficult to distinguish from emerging infection

• An administration or documentation error may not be discovered until arrival

• A horse with an incubating respiratory infection may be vaccinated before the illness becomes obvious

A vaccination given shortly before arrival may satisfy the date component of the national USEF rule, but satisfying the date requirement and making a sound medical decision are not always the same thing.

What Documentation Is Required?

The required evidence depends on who administered the vaccine.

Vaccines Administered by a Veterinarian

When a veterinarian administered the vaccines, the exhibitor must be able to provide veterinary documentation confirming:

• The horse received the required vaccinations

• The names of the vaccines

• The dates of administration

The published rule does not specifically require the vaccine serial number and expiration date on veterinarian-issued documentation, although including this information creates a stronger and more complete medical record. (USEventing)

A practical veterinary certificate should ideally also include:

• Horse’s registered or competition name

• USEF identification number

• Microchip number, where available

• Owner’s name

• Vaccine brand and diseases covered

• Administration date

• Batch or lot number

• Veterinarian’s name, signature and practice details

The horse’s name on the vaccination record should match the name used for the competition entry. Previous names, barn names and ownership changes can create unnecessary confusion at check-in.

Vaccines Administered by an Owner or Agent

USEF provides a documentation pathway for vaccines administered by someone other than a veterinarian.

The exhibitor must be able to provide:

• A receipt for the vaccine purchase

• The signature of the owner or agent with care, custody and control of the horse

• The name of the vaccine

• The vaccine serial number

• The vaccine expiration date

• The date the vaccine was administered

A credit card statement showing a purchase from a feed store is not enough if it does not identify the vaccine and required product information. (USEventing)

Does USEF Allow Owners to Vaccinate Their Own Horses?

The documentation rule recognises vaccination by a person other than a veterinarian.

That does not mean every owner-administered vaccination is automatically medically appropriate. Correct storage, maintenance of the cold chain, injection technique, product selection, administration route and recognition of adverse reactions still matter.

It also does not override state laws or product restrictions. From both a health and documentation perspective, veterinarian-administered vaccination usually creates the least room for disagreement.

What Is the Best Way to Store the Records?

Keep at least two copies:

1. A digital copy accessible from your phone

2. A printed backup in the vehicle, tack trunk or competition folder

The digital file should be legible without requiring access to an old email account, clinic portal or unreliable mobile signal.

A useful competition health folder should contain:

• Influenza and EHV vaccination certificate

• Negative Coggins documentation

• Certificate of veterinary inspection when required

• Medical exemption letter and temperature log, if applicable

• Horse identification and microchip information

• Emergency veterinary contacts

• Any event-specific health declaration

Paperwork is not the glamorous side of equestrian sport, but neither is driving home before the first trot-up because the correct invoice is sitting in someone else’s inbox.

What If the Horse Cannot Be Vaccinated?

The GR845 medical exemption pathway is written for a horse that cannot receive one or both required vaccines because of a history of adverse reactions.

The exhibitor must be able to provide:

• A letter from a veterinarian on official letterhead

• A statement that the horse cannot be vaccinated because of medical concerns

• A temperature log recorded twice daily for the seven days before entering the competition grounds

• Twice-daily temperature recordings throughout the horse’s time on the grounds

The temperature log must be available when requested by competition management, the steward or the technical delegate. (USEventing)

Is a Veterinary Letter by Itself Enough?

No. Under the published rule, the exemption pathway includes both the veterinary letter and the required temperature records.

A letter saying “this horse should not be vaccinated” without the seven-day pre-arrival temperature log may leave the horse noncompliant.

Does the Exemption Guarantee Entry?

Not necessarily.

The exemption satisfies the specific GR845 pathway when properly documented, but competitors must also comply with biosecurity measures imposed by USEF, competition management and local, state or federal animal-health authorities.

During an outbreak, additional movement restrictions, testing, isolation or entry conditions may apply. Contact the competition in writing before transporting an exempt horse. (USEF)

Can Antibody Titres Replace Vaccination?

The current USEF rule does not list antibody titres as an alternative to vaccination documentation or the medical exemption process.

The AAEP also does not currently recommend using antibody titres to decide whether most equine boosters are required because validated protective thresholds have not been established for most equine diseases. A measurable antibody concentration does not necessarily prove that the horse will be protected under field conditions. (AAEP)

Can Competition Management Require More Than GR845?

There are two separate issues.

The vaccination rule states that competition management cannot simply amend or enhance the GR845 vaccination requirements without prior approval from the USEF Veterinary Committee.

However, competitors must also comply with separate biosecurity and equine-health measures imposed by USEF, competition management and relevant government animal-health authorities. (USEventing)

Depending on disease activity, a competition may require additional measures such as:

• Health declarations

• Several days of temperature records

• Veterinary inspection on arrival

• Diagnostic testing

• Isolation of horses with fever

• Restrictions affecting horses from particular premises or regions

• Negative Coggins documentation

• Certificates of veterinary inspection

• Return-to-competition declarations following an EHV exposure

These requirements do not necessarily rewrite the vaccine rule. They are separate disease-control measures.

Always review the current:

• USEF rulebook

• Competition prize list

• Competitor updates

• Venue requirements

• Destination state requirements

• Disease alerts affecting the horse’s home farm or travel route

The 2026 USEF rulebook is the current competition-year rulebook, but USEF also warns competitors to consult the latest version because changes and presidential modifications can occur during the year. (US Equestrian)

What Is the Difference Between USEF and FEI Vaccination Rules?

USEF national rules and FEI international rules should not be treated as interchangeable.

Requirement	USEF national competition	FEI competition
Vaccines addressed by the competition rule	Equine influenza and EHV	Equine influenza
General booster window for entry	Both within six months before entering the stables	Influenza booster within six months plus 21 days before arrival
Restriction immediately before arrival	GR845 does not state the FEI seven-day restriction	Influenza vaccine must not be administered within seven days before arrival
Primary series	Follow veterinarian, manufacturer and accepted vaccination guidance	For a primary course started from January 1, 2024: V1, V2 21 to 60 days later, then V3 within six months plus 21 days of V2
Record location	Acceptable USEF vaccination documentation	FEI passport, with influenza information also recorded in the FEI HorseApp
Maximum later booster interval	USEF entry requirement remains within six months	Subsequent boosters at no more than 12-month intervals, while competing horses must remain within the six-month plus 21-day event window

FEI horses must comply with detailed passport and influenza-series requirements. Since February 1, 2025, FEI influenza vaccination details must also be recorded in the FEI HorseApp. (USEF)

A horse entered in both FEI and national USEF classes may need to satisfy both systems. An FEI passport showing influenza compliance does not, by itself, demonstrate that the horse has met the national USEF EHV requirement. (USEF)

Does USEF Vaccination Compliance Replace a Coggins Test or Health Certificate?

No.

Vaccination documentation, a Coggins test and a certificate of veterinary inspection serve different purposes.

Interstate transport requirements vary by destination, but commonly include:

• A negative equine infectious anaemia test, often called a Coggins test

• A certificate of veterinary inspection issued within the required period

• Identification matching the horse being transported

• Additional destination-specific disease requirements

USEF advises competitors to verify the requirements of both the destination state and the final venue before travelling. (USEF)

A vaccination certificate cannot substitute for a Coggins result. A Coggins result cannot substitute for influenza and EHV documentation.

Upcoming Separate Requirement: USEF Microchipping

Vaccination is not the only health-compliance issue changing.

Beginning December 1, 2026, all horses competing in USEF-licensed or endorsed competitions will be required to have a 15-digit ISO 11784/11785-compliant microchip recorded with USEF.

This is a separate requirement from GR845 and was not yet in force on July 20, 2026, but owners competing later in the year should prepare now rather than discovering the rule after entries close. (USEF)

How Ready Is Your Horse to Enter a USEF Competition?

Low Risk: Ready to Travel

The horse:

• Is more than seven months old

• Has documented EIV and EHV vaccination within six months of entry

• Has records that clearly identify the horse

• Has all required Coggins, health and travel documents

• Is bright, afebrile and showing no infectious disease signs

Action: Carry digital and paper copies and continue routine temperature monitoring.

Moderate Risk: Vaccinated but Paperwork Is Unclear

The horse was vaccinated, but:

• The certificate uses a different name

• The administration date is missing

• The vaccine product is unclear

• The record does not show both EIV and EHV

• The invoice belongs to a group of horses without identifying which horse received the vaccine

• The owner-administered record lacks the receipt, serial number or expiration date

Action: Resolve the documentation before loading. Ask the veterinarian, supplier or competition management what will be accepted.

High Risk: Probably Noncompliant

The horse:

• Is outside the six-month window

• Has documentation for only one of the two required vaccines

• Has no reliable record

• Has an incomplete owner-administered record

• Has a medical exemption letter but no temperature log

Action: Contact the veterinarian and competition management immediately. Do not assume the issue can be fixed at the gate.

Critical Health Risk: Do Not Travel

The horse has:

• An unexplained temperature above 101.5°F, or approximately 38.6°C

• Coughing

• Nasal discharge

• Marked lethargy

• Reduced appetite

• Enlarged lymph nodes

• Recent exposure to an infectious horse

• Hindlimb weakness

• Incoordination

• Urinary dysfunction

• Reduced tail tone or other neurological abnormalities

Action: Isolate the horse and contact a veterinarian. Do not transport the horse to a competition simply because the paperwork is current.

USEF requires unexplained temperatures above 101.5°F to be reported at competition grounds, with affected horses isolated or removed according to the applicable protocol. (USEF)

When Is This an Emergency?

Seek urgent veterinary assessment if the horse develops:

• Difficulty standing

• Progressive incoordination

• Hindlimb weakness

• Loss of bladder control

• Severe depression

• Breathing difficulty

• A rapidly increasing fever

• Collapse

• Multiple affected horses on the same property

Neurological signs associated with possible EHM require immediate isolation and veterinary involvement. Notify competition management promptly if the horse is already on the grounds.

Do not walk an ataxic horse through a busy stable area to “see if they improve.” Restrict access, protect handlers and wait for veterinary instructions.

What Should You Do Before a USEF Competition?

Six to Eight Weeks Before Arrival

1. Check the exact date the horse will enter the stables.

2. Review the dates of both EIV and EHV vaccination.

3. Confirm that the horse has completed an appropriate primary series.

4. Check Coggins and interstate travel requirements.

5. Review the prize list and current health notices.

6. Determine whether the event includes FEI classes.

Two to Four Weeks Before Arrival

1. Administer any required booster under veterinary guidance.

2. Confirm that the record identifies both required diseases.

3. Obtain the final vaccination certificate.

4. Check that the horse’s name and identification match the entry.

5. Avoid unnecessary contact with unfamiliar horses.

AAEP guidance recommends administering necessary vaccines at least 14 days before likely exposure whenever possible. (AAEP)

Seven Days Before Arrival

For a horse using the medical exemption:

• Begin twice-daily temperature recording

• Record the time and actual temperature

• Do not simply write “normal”

• Keep the veterinary exemption letter with the log

For routinely vaccinated horses, temperature monitoring is still sensible. USEF best-practice guidance recommends verifying that horses remain clinically healthy and below 101.5°F before an event. (USEF)

Before Loading

Check:

• Rectal temperature

• Appetite

• Energy level

• Coughing

• Nasal discharge

• Limb coordination

• All health paperwork

• Digital backups

• Event updates or disease alerts

A horse with fever or respiratory signs should not be loaded while you “see how they go on the journey.”

While on the Grounds

• Use individual water and feed buckets

• Avoid communal troughs

• Do not share tack, grooming equipment or towels

• Limit nose-to-nose contact

• Clean hands between horses

• Take and record temperatures regularly

• Report fever or suspicious signs immediately

• Clean and disinfect the trailer between groups of horses

USEF currently encourages twice-daily temperature monitoring at competitions and immediate reporting of a temperature above 101.5°F. (USEF)

After Returning Home

Continue monitoring the horse for fever, coughing, nasal discharge, lethargy or neurological abnormalities.

Where practical, returning horses should initially be managed separately from vulnerable resident horses, particularly broodmares, foals and horses that did not travel. Current USEF EHV guidance recommends quarantine of new and returning horses before full integration into the home population. (USEF)

Common USEF Vaccination Mistakes

Calling EIV and EHV Core Vaccines

They are required for USEF competition, but the AAEP classifies them as risk-based vaccines. Tetanus, EEE/WEE, West Nile virus and rabies remain the US core vaccines.

Calculating From the First Class

The relevant date is when the horse enters the competition stables, which may be several days before the first class.

Assuming “Every Six Months” Means Twice Per Calendar Year

The date of each particular arrival must fall within the six-month window.

Carrying Only a Purchase Receipt

For owner-administered vaccination, the required record also includes the vaccine name, serial number, expiration date, administration date and appropriate signature.

Adding Serial-Number Requirements to Veterinary Records

Serial and expiration information are useful, but the published rule specifically requires the vaccine names and dates for veterinarian-administered vaccines. The more detailed owner-administered pathway has the explicit serial-number requirement.

Bringing an Exemption Letter Without Temperature Records

The letter and twice-daily logs form one exemption pathway. One does not replace the other.

Believing EHV Vaccination Prevents EHM

No current vaccine is labelled to prevent neurological EHV. Vaccination must be combined with temperature surveillance and biosecurity.

Assuming USEF and FEI Rules Are Identical

They involve different documentation systems, intervals and disease requirements.

Transporting a Sick Horse Because the Records Are Current

Vaccination compliance does not prove that the horse is healthy, non-infectious or fit to travel.

Frequently Asked Questions

Does a combined influenza and rhinopneumonitis vaccine meet USEF requirements?

Usually, provided the documented product contains both required components and the record clearly shows that the horse received EIV and EHV vaccination within the required period. Ambiguous records should be confirmed with the veterinarian or competition management before travel.

Can I vaccinate my own horse for a USEF show?

The rule permits a non-veterinarian documentation pathway. You will need the signed purchase receipt, vaccine name, serial number, expiration date and administration date. This does not remove the need for correct handling, storage and administration.

How many days before a USEF show can I vaccinate?

National GR845 does not state the FEI seven-day pre-arrival restriction. However, vaccination should ideally be completed at least 14 days before likely exposure so that immunity can develop and any reaction can resolve. FEI competitors must follow the separate FEI timing rule. (AAEP)

Can a Coggins test replace the vaccination certificate?

No. A Coggins test screens for equine infectious anaemia. It does not document vaccination against influenza or EHV.

Can a horse compete with a medical vaccine exemption?

Potentially, provided the horse meets the GR845 exemption requirements, including the veterinary letter and twice-daily temperature records. Additional event, state or outbreak restrictions may still affect whether the horse can enter.

Final Thoughts

Under the current USEF rule, horses more than seven months old must have documented equine influenza and equine herpesvirus vaccination within the six months before entering the competition stables.

The paperwork requirements depend on who administered the vaccines, and medical exemptions require more than a veterinary letter. They also require twice-daily temperature logs for the seven days before entry and throughout the competition.

The bigger clinical point is that compliance and protection are not the same thing. A vaccination certificate does not guarantee complete immunity, prevent neurological EHV or prove that a horse with a fever is safe to travel.

Check the dates early, complete the paperwork properly and monitor the horse rather than treating vaccination as a box-ticking exercise. Show day is an extraordinarily expensive place to discover that one date, batch number or temperature log is missing.

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ASK A VET™ can help you organise vaccination certificates, schedule booster reminders, store competition health documents and track temperatures before and after travel. A horse with fever, coughing or neurological signs still requires direct veterinary examination and should not be transported to a competition.