Can EHV Vaccination Prevent Neurologic Disease in Horses?

By Dr Duncan Houston

EHV vaccination can reduce respiratory disease, abortion risk and viral shedding, but it cannot guarantee protection from the neurologic form.

Equine herpesvirus is one of the most frustrating infectious diseases in horses because vaccination helps, but it does not solve everything.

That is especially true for EHV-1 myeloencephalopathy, often called EHM, the neurologic form of equine herpesvirus. This is the form owners fear most because it can cause hindlimb weakness, ataxia, urine dribbling, recumbency, and in severe outbreaks, euthanasia or death.

The key point is this: EHV vaccination is still useful, but it should never be treated as a force field. It is one layer of protection. The other layers are biosecurity, temperature monitoring, rapid isolation, movement control, and veterinary testing when fever or neurologic signs appear.

Quick Answer

EHV vaccination helps reduce the severity and duration of respiratory disease, helps reduce EHV-1 abortion risk when appropriate vaccines are used in pregnant mares, and may reduce nasal shedding and viremia. However, there are currently no licensed vaccines labelled to prevent neurologic EHV-1 disease, also known as EHM.

If your horse has fever, hindlimb weakness, wobbliness, urine dribbling, difficulty rising, or sudden neurologic signs, do not rely on vaccination history for reassurance. Isolate the horse and call your veterinarian immediately.

What Is Equine Herpesvirus?

Equine herpesvirus refers to a group of herpesviruses that infect horses. The two most important types in routine equine health discussions are EHV-1 and EHV-4.

EHV-1 can cause:

• Respiratory disease
• Abortion
• Fatal neonatal disease
• Neurologic disease, called equine herpesvirus myeloencephalopathy or EHM

EHV-4 is more commonly associated with respiratory disease and only rarely with abortion or neurologic disease. AAEP notes that EHV-1 and EHV-4 infect the respiratory tract and can range from subclinical infection to severe respiratory disease, while EHV-1 can also cause abortion, fatal neonatal disease and EHM.

One of the reasons EHV is difficult to control is that herpesviruses can become latent. That means the virus can persist silently in the horse and reactivate later, especially during stress, illness, transport, training changes, breeding stress, or commingling. AAEP states that these viruses establish latent infection in most horses and may reactivate with short-term shedding when stressed.

What Is EHM?

EHM stands for equine herpesvirus myeloencephalopathy.

It is the neurologic form of EHV-1 infection. It occurs when EHV-1 associated viremia and vascular damage affect the central nervous system, especially the spinal cord. AAEP describes EHM as resulting from cell-associated viremia leading to vasculitis, thrombosis, infarction within central nervous system blood vessels, and neurologic disease.

Signs of EHM can include:

• Fever before neurologic signs
• Hindlimb incoordination
• Ataxia
• Weakness
• Urine retention or dribbling
• Bladder atony
• Recumbency with inability to rise
• Rarely, cranial nerve signs, seizures, or brainstem signs

AAEP warns that many EHM cases do not fit the classic description of hindlimb ataxia and urinary incontinence, which is clinically important because early cases can be missed if owners only look for the textbook version.

In practice, what worries vets most is a horse with fever followed by wobbliness, hindlimb weakness, urine dribbling, or difficulty standing. That pattern should always be treated seriously.

What Can EHV Vaccines Actually Do?

EHV vaccines are useful, but their purpose needs to be understood correctly.

AAEP states that indications for EHV-1 and EHV-4 vaccines include prevention of EHV-1 abortion and reduction of severity and duration of respiratory tract disease. AAEP also notes that EHV vaccines can reduce nasal shedding and reduce development of viremia, with the goal of reducing spread within horse populations and reducing disease severity in individuals.

That means vaccination may help by:

• Reducing respiratory disease severity
• Reducing respiratory disease duration
• Reducing nasal viral shedding
• Reducing viremia
• Reducing EHV-1 abortion risk in pregnant mares when appropriate labelled vaccines are used
• Helping reduce spread at a population level

But vaccination does not mean:

• Your horse cannot get EHV
• Your horse cannot shed EHV
• Your horse cannot develop neurologic disease
• An outbreak can be controlled by vaccination alone
• A febrile horse can be ignored because it is vaccinated

This is where owners sometimes get caught. A vaccinated horse with fever still matters. A vaccinated horse with neurologic signs is still an emergency.

Can EHV Vaccination Prevent EHM?

No vaccine is currently licensed with a label claim to prevent neurologic EHV-1 disease.

AAEP states directly that there are currently no licensed vaccines labelled for prevention of neurologic EHV-1 infection, and EDCC states there is currently no vaccine labelled for prevention of the neurologic form of EHV-1.

That does not mean vaccination is useless for EHM risk. The logic is more nuanced.

Because EHM is linked to viremia and viral spread through the body, vaccines that reduce viremia and nasal shedding may have theoretical value in reducing spread or severity. AAEP states that some vaccines reduce nasal shedding and viremia and therefore have theoretical value against EHM by reducing viremia, as well as reducing environmental spread by lowering viral shedding.

The important word is theoretical.

The practical veterinary message is:

Vaccination may reduce some risk factors around EHV spread and severity, but strict biosecurity controls outbreaks better than any vaccine protocol.

AAEP states that strict biosecurity practices including isolation of infected horses, quarantine of affected premises, and monitoring of at-risk populations are currently more effective at controlling outbreaks than any existing vaccination protocol.

Why Do Some Vaccinated Horses Still Get EHM?

This is one of the hardest things for owners to accept.

Vaccines do not create perfect sterilising immunity against EHV. AAEP states that immunity against EHV is complex and post-vaccinal antibodies do not necessarily ensure protective immunity against clinical disease.

There are several reasons vaccinated horses may still become infected or develop disease:

• Immunity may be short-lived
• The horse may have been exposed before the vaccine response developed
• The horse may have intense exposure in a high-risk environment
• EHV can reactivate from latency
• Vaccines reduce, but do not eliminate, nasal shedding or viremia
• Older horses and heavily commingled populations can be higher risk
• EHM risk is influenced by factors beyond simple antibody levels

A 2024 systematic review of EHV-1 vaccination studies found that evidence quality varied, sample sizes were often small, and commercial and experimental vaccines appeared to only minimally reduce the incidence of clinical disease associated with EHV-1 infection.

That does not mean “do not vaccinate.”

It means “do not overpromise what vaccination can do.”

What About Reports of Vaccination and Neurologic Risk?

This section needs careful wording.

Some outbreak investigations have reported an association between prior EHV-1 vaccination and EHM development, but association does not prove causation. AAEP states that an association between EHV vaccination and EHM has been reported in multiple outbreak investigations, but the mechanism remains unknown and there are not enough controlled challenge studies to revise existing vaccination recommendations on that basis.

In plain English:

• Vaccinated horses can still develop EHM
• Some outbreaks found prior vaccination among affected horses
• This does not prove the vaccine caused EHM
• Vaccination may simply be more common in high-risk populations, such as show horses, racehorses, breeding farms, and horses that travel
• Current guidance has not changed to say EHV vaccines cause EHM

The wrong takeaway is: “Vaccines cause neurologic EHV.”

The better takeaway is: EHV vaccination must be used as part of a risk-based plan, not as a stand-alone outbreak shield.

EHV Vaccination Risk Framework

Risk level	What it looks like	What vaccination means	What to do
Low risk	Mature horse, low movement property, no pregnant mares, no current outbreak	Frequent EHV vaccination may not be needed unless local risk changes	Discuss routine risk-based vaccination with your vet
Moderate risk	Young horse, training barn, agistment property, periodic travel, mixed horse populations	Vaccination may help reduce respiratory disease and shedding	Maintain appropriate boosters and biosecurity
High risk	Racehorse, show horse, sales horse, breeding farm, contact with pregnant mares, frequent movement	Six-monthly boosters are commonly recommended in many high-risk groups	Plan boosters before exposure, not during panic
Critical	Fever, neurologic signs, abortion, known exposure, active outbreak	Vaccination is not the immediate solution	Isolate, stop movement, call your vet and follow testing or quarantine protocols

The key decision point: vaccination is a prevention tool, not an emergency treatment.

Which Horses Are Usually Considered Higher Risk?

EHV vaccination decisions should be based on exposure risk, age, pregnancy status, travel, movement, and herd situation.

AAEP recommends six-monthly revaccination for certain higher-risk groups, including horses under five years of age, horses on breeding farms or in contact with pregnant mares, horses at facilities with frequent movement on and off the premises, and performance or show horses in high-risk settings such as racetracks or show grounds.

Higher-risk horses may include:

• Racehorses
• Show horses
• Young horses in training
• Horses under five years old
• Horses on busy agistment or boarding properties
• Horses travelling frequently
• Horses attending clinics, shows, sales, camps, or competitions
• Horses on breeding farms
• Pregnant mares
• Horses living with or near pregnant mares
• Horses returning from high-risk events

The horse that never leaves a quiet property is not the same risk as the horse travelling to packed show grounds every second weekend.

What Is the EHV Vaccine Schedule for Adult Horses?

For adult non-breeding horses with previous EHV vaccination, frequent vaccination of mature non-pregnant horses is generally not indicated unless risk is increased. AAEP specifically identifies several higher-risk groups where six-monthly revaccination is recommended.

For adult horses that are unvaccinated or have unknown vaccine history, AAEP recommends a primary series of two or three doses depending on product, with a four-week interval between doses.

The practical approach is:

• Low-risk mature horse: discuss whether routine EHV vaccination is needed
• High-risk performance or show horse: often six-monthly boosters
• Busy training or boarding facility: risk-based booster planning
• Horses entering events: check facility or competition vaccination rules
• Horses recently sick or exposed: do not vaccinate casually without veterinary advice

Timing matters. A booster given the day before exposure is not the same as a planned vaccination schedule that allows the immune response to develop.

What Is the EHV Vaccine Schedule for Pregnant Mares?

Pregnant mares are a special group because EHV-1 can cause abortion, often late in pregnancy and sometimes without obvious warning signs.

AAEP recommends vaccinating pregnant mares during the fifth, seventh, and ninth months of gestation using an inactivated EHV-1 vaccine licensed for prevention of abortion. Many veterinarians also recommend a dose during the third month of gestation, and some recommend a dose at breeding. AAEP also notes that vaccination four to six weeks before foaling is commonly practiced to enhance colostral immunoglobulin transfer and reduce respiratory disease in foals.

In practice, broodmare vaccination should be planned with your veterinarian because the exact schedule can depend on:

• Country
• Product label
• Farm history
• Local outbreak risk
• Mare vaccination history
• Breeding season timing
• Whether the mare is on a high-risk stud farm
• Whether horses are moving on and off the property

Do not freestyle broodmare EHV vaccination. The timing is too important.

What Is the EHV Vaccine Schedule for Foals?

AAEP recommends foals receive a primary series of three doses of inactivated EHV-1 or EHV-4 vaccine or modified-live EHV-1 vaccine, beginning at four to six months of age, with a four-week interval between the first and second doses, and the third dose at ten to twelve months of age.

Foal vaccine planning should consider:

• Mare vaccination status
• Maternal antibody interference
• Farm risk
• Weaning timing
• Movement and sales
• Respiratory disease pressure
• Whether the foal is part of a high-turnover population

Young horses are often where respiratory EHV circulates most easily, especially when horses from different sources are mixed.

Which EHV Vaccine Should You Choose?

There is no single “best” EHV vaccine for every horse.

Broadly, EHV vaccines include:

• Inactivated vaccines for respiratory disease
• Inactivated vaccines labelled for both respiratory disease and abortion
• Modified live EHV-1 vaccines for respiratory disease

AAEP notes that dual-labelled EHV vaccines for respiratory disease and abortion contain higher antigenic loads and induce more robust antibody responses than vaccines labelled for respiratory disease only. AAEP also states that vaccines with the greatest ability to reduce nasal shedding and viremia include vaccines licensed for abortion control, Calvenza, and the modified-live vaccine Rhinomune.

That does not mean owners should choose based on brand names from an article.

The right vaccine depends on:

• The horse’s age
• Pregnancy status
• Travel schedule
• Local outbreak risk
• Event requirements
• Prior reaction history
• Whether EHV-1 abortion prevention matters
• Whether the horse is in a high movement group
• Your veterinarian’s experience with regional disease patterns

The product matters, but the plan matters more.

Should You Vaccinate During an EHV Outbreak?

This is a veterinary decision, not a blanket yes or no.

AAEP states that controlled, peer-reviewed research does not currently exist to determine whether vaccinating horses during an EHV outbreak reduces transmission. AAEP also says vaccination of at-risk populations may limit viral spread by reducing nasal shedding, but strict biosecurity remains more effective for outbreak control than any existing vaccination protocol.

In practical terms:

• Do not vaccinate a sick horse casually
• Do not vaccinate a febrile horse without veterinary direction
• Do not assume vaccination will stop an active outbreak
• Do not use vaccination instead of isolation and quarantine
• Do not move horses because they “just got boosted”
• Do involve your vet or local animal health authority during an outbreak

For horses that were naturally infected and recovered, AAEP notes that immunity can be expected to last three to six months, longer in older horses, and booster vaccination can be resumed six months after disease occurs.

What Are the Symptoms of EHV Infection?

EHV signs vary depending on whether the horse has respiratory disease, abortion, neonatal disease, or EHM.

Respiratory signs may include:

• Fever
• Lethargy
• Reduced appetite
• Nasal discharge
• Cough
• Enlarged mandibular lymph nodes
• Conjunctivitis
• Lower limb swelling

AAEP lists fever, coughing, nasal discharge, lethargy, anorexia, lymph node enlargement, ocular disease, and lower limb swelling among signs of EHV respiratory disease.

Neurologic signs may include:

• Hindlimb weakness
• Wobbliness
• Ataxia
• Urine dribbling
• Urine retention
• Recumbency
• Difficulty rising
• Rare cranial nerve signs or seizures

Abortion can occur from two weeks to several months after exposure, often in late pregnancy, and mares may show no warning signs before aborting.

Why Temperature Monitoring Matters So Much

Fever is one of the most important early EHV clues.

AAEP states that fever can be biphasic and transient. The first fever peak may occur one to two days after exposure and can precede respiratory signs. A second fever phase around six to seven days after exposure may precede systemic viremia. AAEP recommends twice daily temperature monitoring in at-risk horses to reduce the chance of missing fever.

This is a big practical point.

A horse can look mostly normal, have a fever, and still be the horse you needed to isolate yesterday.

During an outbreak or after a high-risk event, twice daily temperatures are not overkill. They are how you catch the quiet cases before they become the whole barn’s problem.

When Is EHV an Emergency?

EHV should be treated as urgent if your horse has:

• Fever after known exposure
• Fever during an outbreak
• Hindlimb weakness
• Ataxia
• Wobbliness
• Urine dribbling
• Inability to urinate
• Recumbency
• Difficulty rising
• Sudden neurologic signs
• Abortion
• Sick newborn foal
• Rapid deterioration
• Respiratory distress
• Multiple horses with fever on one property

A horse with neurologic signs should be isolated and assessed immediately. EDCC lists fever, nasal discharge, lethargy, late-term abortion, neonatal death, and neurologic disease as key EHV-1 signs, while AAEP states horses showing clinical signs consistent with EHV infection, especially fever or neurologic signs, should be tested. (Equine Disease Communication Center)

The clinical rule is simple: fever during an EHV risk period is not something to casually watch for days. Fever plus neurologic signs is an emergency.

How Do Vets Diagnose EHV?

Diagnosis usually involves PCR testing and clinical assessment.

AAEP recommends testing horses showing signs consistent with EHV infection, especially when febrile or neurologic. Nasal or nasopharyngeal swabs and blood are commonly tested together by qPCR. AAEP states that qPCR is more sensitive and faster than virus isolation and is the test of choice for rapid detection during outbreaks.

Testing may include:

• Nasal swab
• Nasopharyngeal swab
• Whole blood or buffy coat sample
• PCR testing
• Virus isolation in selected cases
• Paired serology collected two to three weeks apart
• Abortion tissue testing
• Placental testing
• Necropsy in fatal neurologic or neonatal cases

AAEP also notes that fever can precede both nasal shedding and viremia. If a febrile horse with suspected exposure tests negative initially, AAEP recommends retesting blood and nasal swab PCR 24 to 72 hours later and keeping the horse quarantined until results are available.

That is why one negative test very early does not always end the conversation.

What Else Can Look Like EHV?

EHV can look like several other equine diseases, especially early on.

Important rule-outs include:

• Equine influenza
• Strangles
• Equine rhinitis virus
• Equine viral arteritis
• Bacterial pneumonia
• Guttural pouch disease
• Equine coronavirus
• Botulism
• Cervical spinal cord disease
• Trauma
• Tetanus
• Rabies
• West Nile virus
• Equine protozoal myeloencephalitis
• Toxicity
• Colic causing reluctance to move
• Reproductive causes of abortion
• Placentitis

This matters because the management changes. A horse with influenza, strangles, EHV, West Nile virus, botulism, rabies risk, or trauma may all look “off” at first, but the testing, biosecurity, treatment, and public health implications are very different.

A wobbly horse is not automatically EHV. But in the wrong setting, EHV must be taken seriously until your vet can rule it in or out.

What Should You Do If You Suspect EHV?

1. Isolate the horse immediately

Do not wait for lab results before basic isolation.

Keep the horse away from others, stop shared equipment, and avoid unnecessary movement.

2. Stop horse movement on and off the property

Movement spreads outbreaks.

AAEP lists movement during confirmed or potential outbreak situations as a risk factor for development of EHV infection, especially before quarantine restrictions are properly applied or released.

3. Take temperatures twice daily

Record temperature morning and evening.

A temperature above 101.5 F or 38.6 C is considered fever in AAEP EHV guidance.

4. Call your veterinarian

Give your vet:

• Temperature records
• Vaccination history
• Travel history
• Event attendance
• Contact with sick horses
• Whether any horses have aborted
• Whether any horses have neurologic signs
• Timeline of signs
• Number of horses affected

5. Handle sick or exposed horses last

Use separate buckets, halters, grooming tools, lead ropes, rugs, feed tubs, and cleaning gear.

EDCC states that EHV spreads through aerosol particles from nasal discharge and contaminated surfaces including people, clothing, feed, water, equipment, and stalls. (Equine Disease Communication Center)

6. Clean and disinfect properly

Contaminated surfaces and equipment matter. AAEP states that fomites such as clothing, footwear, grooming equipment, tack, feed and water sources, stalls, wash racks, and tie points can transmit EHV virus.

7. Do not vaccinate, medicate, or move horses without guidance

During an outbreak, every action can affect interpretation, risk, or quarantine.

The temptation to “do something” is strong. With EHV, the best first something is usually isolation, temperature monitoring, and calling your vet.

How Long Should Horses Be Quarantined?

Quarantine timing depends on the disease form, local authority rules, testing, and whether new signs appear.

AAEP states that respiratory shedding typically lasts seven to ten days but can be longer, and a period of 14 to 28 days after resolution of clinical signs in all exposed horses may be necessary before release from movement restrictions or isolation.

For confirmed EHM, AAEP states horses should be isolated immediately and the premises quarantined under animal health official guidance for a minimum of 28 days. During that period, all horses should be monitored at least twice daily for fever or other signs, and fever, abortion, or new neurologic disease can restart the 28-day quarantine period.

In many regions, EHV or EHM may be reportable. AAEP notes that EHV and EHM are reportable to the State Animal Health Official in many states, and official quarantine, testing, and biosecurity requirements may apply.

The safest rule: follow your veterinarian and local animal health authority, not stable gossip.

Common Mistakes With EHV Vaccination and Outbreaks

Mistake 1: Thinking vaccination prevents all EHV disease

Vaccination reduces risk and severity in specific ways, but it does not completely prevent EHV infection, shedding, or EHM.

Mistake 2: Ignoring fever in a vaccinated horse

A vaccinated horse with fever during an outbreak or after a high-risk event should still be isolated and assessed.

Mistake 3: Vaccinating during an outbreak without a plan

Outbreak vaccination is risk-based and vet-led. It should not replace isolation, quarantine, and monitoring. AAEP states strict biosecurity is more effective at outbreak control than any vaccination protocol.

Mistake 4: Moving horses too early

Movement during suspected or confirmed outbreak situations increases risk. Waiting for proper quarantine release matters.

Mistake 5: Not taking temperatures twice daily

Fever can be brief and easy to miss. During EHV risk periods, twice daily temperature records are one of the most useful tools you have.

Mistake 6: Assuming all neurologic horses have EHM

EHM is important, but neurologic horses need a proper differential list. West Nile virus, trauma, EPM, botulism, rabies risk, toxicity, and other causes may need to be considered.

Mistake 7: Using vaccination as the whole prevention strategy

The best prevention is layered: vaccination, biosecurity, travel hygiene, quarantine, event caution, and rapid isolation of sick horses.

How To Reduce EHV Risk Before Travel or Shows

For performance horses and show horses, prevention should start before the float is packed.

Practical steps include:

• Keep EHV vaccination current according to risk
• Discuss six-monthly boosters for high-risk horses
• Avoid travelling horses with fever or respiratory signs
• Take temperatures before departure
• Take temperatures twice daily during high-risk events
• Avoid nose-to-nose contact with unfamiliar horses
• Do not share buckets, feed tubs, nose cloths, tack, or grooming gear
• Improve ventilation where possible
• Clean and disinfect trailers between trips
• Quarantine or monitor horses after return when risk is high
• Keep written records of horse movement and temperatures

AAEP identifies performance and show horses in high-risk situations, such as racetracks or show grounds, as one of the groups recommended for six-monthly revaccination.

The glamorous part of horse travel is the competition.

The important part is not letting one febrile horse turn the whole event into a biosecurity group project.

How To Reduce EHV Risk on Breeding Farms

Breeding farms need special care because EHV-1 can cause abortion and neonatal disease.

A strong breeding farm plan includes:

• Vaccinating pregnant mares at appropriate gestation months
• Managing mare groups to reduce unnecessary mixing
• Quarantining new arrivals
• Separating pregnant mares from high-movement horses
• Monitoring fever and respiratory signs
• Managing aborted fetal material as infectious
• Testing aborted fetus and placenta where indicated
• Cleaning and disinfecting contaminated areas
• Reducing stress and unnecessary movement
• Keeping excellent vaccination and breeding records

AAEP states that aborted fetuses, fetal membranes, and fetal fluids are significant sources of virus, and horses in the paddock or pasture where abortion occurs should be removed and isolated from unexposed horses.

This is not the time for casual cleanup. EHV abortion should trigger immediate veterinary involvement and strict biosecurity.

Myth vs Reality

Myth	Reality
“EHV vaccines prevent neurologic disease.”	No vaccine is currently labelled to prevent EHM.
“Vaccinated horses cannot spread EHV.”	Vaccines may reduce shedding, but they do not eliminate the risk.
“A horse with EHV will always look obviously sick.”	Fever may be brief, subtle, or the only early sign.
“One negative early PCR test clears the horse.”	If fever precedes shedding or viremia, retesting 24 to 72 hours later may be needed.
“Vaccination can control an active outbreak.”	Strict biosecurity, isolation, quarantine, and monitoring are more effective than vaccination alone.
“EHV is only a respiratory disease.”	EHV-1 can also cause abortion, fatal neonatal disease, and neurologic disease.

Frequently Asked Questions

Can EHV vaccination prevent EHM?

No current vaccine is licensed to prevent neurologic EHV-1 disease, or EHM. Vaccination may reduce nasal shedding and viremia, which may help reduce spread or disease severity, but it does not guarantee protection from neurologic disease.

Should performance horses get EHV boosters every six months?

Many high-risk horses, including performance or show horses in high-risk settings such as racetracks or show grounds, are recommended for six-monthly revaccination by AAEP. Your veterinarian should tailor this to your horse’s risk and local requirements.

Should pregnant mares be vaccinated for EHV-1?

Yes, pregnant mares commonly receive an inactivated EHV-1 vaccine labelled for prevention of abortion during the fifth, seventh, and ninth months of gestation. Your veterinarian may adjust the schedule based on product label, farm history, and regional risk.

Can a vaccinated horse still get EHV?

Yes. Vaccination can reduce disease severity, duration, shedding, and viremia, but it does not guarantee complete protection. Fever, respiratory signs, or neurologic signs in a vaccinated horse still need veterinary attention.

What is the first sign of EHV?

Fever is often the first warning sign and may occur before nasal discharge, coughing, or neurologic signs. During an outbreak or after exposure, twice daily temperature monitoring is recommended for at-risk horses.

The Bottom Line

EHV vaccination matters, but it has limits.

It can help reduce respiratory disease, abortion risk in pregnant mares, nasal shedding, viremia, and disease severity. It may help reduce spread in a population. But it does not guarantee protection from EHM, and no vaccine is currently labelled to prevent the neurologic form of EHV-1.

The best EHV plan is layered:

• Vaccinate based on risk
• Plan boosters before exposure
• Monitor temperatures during risk periods
• Isolate febrile horses early
• Stop movement during suspected outbreaks
• Test appropriately
• Treat neurologic signs as urgent
• Use biosecurity as the real outbreak control tool

If your horse is vaccinated and healthy, that is reassuring.

If your horse is vaccinated but febrile, wobbly, weak behind, dribbling urine, unable to rise, or linked to an EHV outbreak, vaccination history should not slow you down. Call your veterinarian.

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If you are unsure whether your horse’s EHV vaccination schedule is appropriate, or whether fever, travel exposure, abortion risk, or neurologic signs should trigger urgent action, ASK A VET™ can help you organise the history, track temperatures, and decide when veterinary care should not wait.