Readers Respond: Encountering EPM

More than 1,300 readers of TheHorse.com responded to a poll asking, "Have horses close to you experienced EPM?"

results of poll on incidence of epm

Results were as follows: 
  • Yes, I owned a horse with EPM: 37.80% (502)
  • Yes, a friend owned an EPM horse: 28.39% (377)
  • Yes, there have been many cases around me: 26.28% (349)
  • No: 7.53% (100)

All comments submitted by poll respondents are listed below.

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  • Indy is 5 mo post diagnosis & 3 mo post treatment. Not recovered yet. Small setbacks w/stress. 3+1-
  • yes i own a barrel horse that had epm i am happy to say he recovered wonderfully
  • sadly mine lost the fight. it was in 97, before Marquis and before the Godsend that is the EPM list
  • he recovered to be ridable but not as an eventer
  • Came on after castration of a 3 YO. Treated very early on, before blood test results, with Marquis.
  • Pepper had EPM 10 years ago, recovered, but has problems with lifting left hind leg.
  • The horse was treated with Marquis and recovered enough to be pasture sound.
  • they may recover, but as far as I know are never the same
  • We just had to put our horse to sleep she had the EMP viruse
  • My horse had EPM before Marquis was avail. He got better for awhile but eventually was put to sleep.
  • My Paint Reining mare had EPM about 6 years agol. We used homeopathic remedies . She is recovered.
  • Horse displayed intermittent hindquarter weakness
  • I have never seen a horse fully recover from EPM. So in our equine practice we vaccinate for EPM
  • improved greatly after Marquis treatment
  • I own a mare I bought infected with EPM. Treated with pyrimethamine sulfadiazine.
  • $14,000 in treatment left him blind and preminently nerve damaged but EPM free
  • The horse foundered from the medication w/ an infected protrusion of the coffin bone. Did not survi
  • recovered but not to full racing ability
  • My stallion underwent a spinal tap and tested out weak positive for EPM. After meds, he's okay.
  • I leased one--best horse in the universe. Rest in peace, Woody
  • One of the Morgan gelding I used to ride died from EPM several years ago.
  • The horse was euthanized as was before good tx available.
  • They recently put him down, not EPM related problems.
  • Horse euthanized.
  • EPM isn't yet seen in our area of Canada
  • I knew a woman who boarded her EPM gelding at the same facility as my mare Chantilly.
  • Very subtle signs, caught early, treated and fully recovered to win 2 stakes races.
  • Extremely Pissy Mare ???
  • My horse was treated with Marquis for 60 days. He was rated a 3.5-4 neurologic condition.
  • The horse died 18 months after being diagnosed. Euthanized when unable to stand.
  • I still own her, and with homeopathy she was cured!
  • My horse fully recovered. She is 8 years old.Her personallity has undergone a change but she is full
  • After several treatments the horse fully recovered.
  • yes, she recovered
  • My mare died within 8 weeks of onset despite use of latest drugs.
  • Horse treated with minimal improvement post treatment
  • I wish I knew what EPM is.
  • The mare still has some lingering neurological issues but is mostly recovered.
  • yes I still own my dear Cim-he was treated for 2 months but was too far gone. he walks and eats .
  • This happened 14 years ago and it was a very mild form that responded well to antibiotics.
  • even after the "cure" the horse is not the same
  • Every horse I've known with EPM had owner who stressed out horse. Correlation? Maybe
  • I have had 3 horses diagnosed with EPM. 2 recovered, 1 still has issues.
  • In 1992 my vet suspected EPM - tests were inconclusive-put on meds and recovered
  • I brought Sonny back to full health--he was foxhunting 2 yrs after treatment.
  • My friend;s horse did recover fully
  • 2 vets said it was wobbles. Had he been treated promptly, be might have fully recovered.
  • 1 mo Marquis + 1 mo Navigaotr +2 mo Marquis +2 mo double dose Marquis=blind, unridable, EPM Free
  • Treatment worked very well. She recovered and remained sound to ride.
  • I have 2 fully recovered EPM'rs. If you're dealing with EPM go to epm@yahoogroups.com for help!
  • My friend had no results from meds, we tried the neurostimulator used on humans "Interx" with full r
  • I have seen horses successful recover from EPM with lots of meds and hard work!
  • Yes I currently own a horse with epm. Pray for him that was my rolex horse!
  • Lost horse after over a year of struggle
  • We lost a mare to EPM in'83, hopefully her loss helped develop todays treament options
  • Young OTTB with unrelated symptoms misdiagnosed by vets until massive damage THEN they all said EPM.
  • he didn't make it eventhough he was owned by a vet.
  • My neighbor has a QH mare that contracted EPM, in 2004. She still has neuological signs.
  • The horse seemed to have recovered, but may be in the early stages of a recurrent bout
  • My horse was diagnosed in 2000 with EPM; then relapsed in 2002; replapsed again in April 2007.
  • Rideable the first time; the second time more muscle atrophy and retired.
  • A horse, where I board, "recovered" from EPM. It has some residual paralysis & vision difficulties
  • Yes, horse fully recovered
  • Vets could not determine definate illness before horse was put down. Necropsy concluded it was EPM.
  • My APHA gelding began having "symptoms" around the age of 7, given wrong RX and diag.,not 100% recov
  • Currently own a gelding who was diagnosed and treated for EPM 4 years ago. Is happy and healthy.
  • all the horses recovered
  • no one I know has had a horse withEPM
  • Its been 10 yrs & she's awesome. Used to lean on the wall to stand / jumps courses w/flying chngs
  • yes
  • A freind had a stallion with it. Used herbs and acupuncture.Died of W Nile during recovery.
  • I bought it thin and got it to gain weight then it got severe EPm symptoms and died,she had antibodi
  • Both horses I knew relapsed after treatment and were euthanized.
  • A Full Recovery after many years.
  • this was a heart wrenching experience Ihad a 6 year old tbthat contracted EPM
  • I find this more frequently among competition mounts under stress that travel to shows.
  • They have some kind of crooked ness in their body as a result. One horse still competes well i.
  • Upsetting due to the horse being wobbly in his hind qtrs, but treated & fully recovered.
  • My mare's 10 day treatment of SEFACON ended today. Already looking like a different horse!
  • Friend's horse had to be euthanized
  • he also had Cushing's and had to be euthanized
  • has recovered but still has times when he is not sound
  • I have a 5 year old horse with epm that I ran barrels on. He has not recovered after 1 year.
  • Chose to euthanize that horse due to the cost of treatment.
  • horse survied, but have back stiffness/ vet questioned spinal taps?
  • Mare-twin foals, 1 yr off. V. short stride, cantered sideways. Treated. stifle ligmts. stretched.
  • He was a 20 y/o gelding, w/vet treatment horse still passed in 2 wk period
  • 2 bouts - so far
  • I run a horse program with 20 horses, 14 of them have had EPM. They all fully recovered.
  • My horse was at a lay-up facility and there were a number of EPM retirees there, too!
  • I still may have to put him down.Its been 3 yrs since treatment but he the damage is done.
  • It was awful. The horse was actually not diagnosed with EPM, was given steroids. symptoms exploded!
  • My hoss test'd pos. 4 EPM. Vet said not 2 worry unless hoss showed signs. Didn't/hasn't 9 yrs. later
  • i observed no symptoms
  • Horse treated about 7 years ago with IV organic arsenic and did fully recover with no recurrence
  • We had to euthanize him as he could not keep balanced and was injuring himself when falling.
  • Our horse did not fully recover, we are struggling with the fact that we may have to let him go.
  • An aquaintance does not have the funds(&700.00) to treat her so she suffers, i.e.,uncontrolled urine
  • My experience with an EPM diagnosed horse is the rear being un stable & wobbly was the first clue.
  • Sultan was diagnosed 10 yrs ago - meds from Canada took 6 wks - were too late.
  • My App. got EPM in 2002. I treated & he remains unrideable and retired. Age 27
  • So far so good, knock on wood!
  • My TB at the time of was 3 years old he recently died of cancer at the age of 15.
  • She is a brood mare at a farm in WV.
  • Treated w/Marquis; now on Vita Royal EPS formula and Liquid Nutrient Buffer. Coming back slowly.
  • It affected his brain the most, it was like dementia, it was so sad!! What do you know of a vaccine?
  • EXCUSE ME FOR BEING DUM BUT< Whats EPM?
  • My horse had epm I treated him with Marquis and Navigator. He has fully recovered
  • Some nerological signs. treated horse 4 months, he's better but 100%
  • Insidious off and on rear leg lamesness. Had a blood test done it showed exposure to epm.
  • I had 2 in Aug 2002, and 1 in Oct 2002. All survived, but the first 2 took a yr to do so.
  • horse was treated twice, recovered and had to be treated again, but recovered!
  • I have one horse with EPM twice, and another horse with EPM once
  • I have treated 3 EPM horses, all came back to at least 90% recovered.
  • The horse was 35 years old and did not recover. I put her down when I couldn't maintain her weight.
  • Not confirmed to be EPM, could have been bone fx related to silicone exposure
  • Own horse that experienced EPM twice. Treated w/ Navigator. Ex. recovery both times.
  • Using Viat Royal EPS Formula and Liquid Nutrient Buffer... coming back slowly
  • The horse fully recovered but without meds. After 2 years off work, he is 100%.
  • It was caught early and the horse made a 95+5 recovery and returned to competition.
  • Yes, there was complete recovery, but the tribrissen caused founder which also needed treatment
  • horse was put down
  • Thankfully I have not experienced EPM in any form. Hopefully I never will either.
  • 22 years old and even with treament, had to be put down.
  • my horse was diagnossed with epm right before devon.
  • yearling, fully recovered after one year
  • Horse was treated, but did not recover and was euthanized
  • horse unable to recover -
  • Live in WA and just don't see it.
  • As a farm manager I had 4 thoroughbreds developed EPM. Most recovered completely. One never.
  • Expensive boarding barn -- in at night - out 3 hrs. day
  • A friend's horse had to be put down due to EPM.
  • Yearling filly became recumbent and could not get up within 24 hrs of 1st sx, had to be euthanized
  • We own a 12 yr old gelding that has been treated and recovered from EPM, shown no signs for 1 yr now
  • I've know a couple. The horses are never the same, but very close to it.
  • My Thoroughbred gelding had EPM; he has recovered, but he never gained back his lost weight & muscle
  • I have a horse that is recovered about 90% and is doing wonderful as of now.
  • Unfortunately, EPM proved fatal for my horse despite treatment.
  • Horse maintained for several years, but eventually had to be put down.
  • 1990 Rex was pllaced on Daraprim for approx 30 day recoverd; residual narcolepsy which girthed up.
  • My horse was dragging his back foot when trotting, then he started to become lethargic and depressed
  • Horse had to euthanized 6 weeks after diagnosis
  • A horse in my barn in Apex NC had EPM, she recovered after a year or so and is now back in work.
  • My very reliable hunter became progressively more mentally unstable and was retired.
  • My 3 yr old WB is currently being treated w/Marquis. Hoping for the best!
  • Incredibly sad, the horse was euthanized after 4 weeks of treatment and progressively degerative.
  • symptoms showed just days after purchase.Breeder would not refund $4000.00 pre vet didnt catch EPM
  • Full recovery after 2 rounds of Marquis and time off
  • THREE HORSES WERE TREATED SUCCESSFULLY WITH MARQUIS AND ONE DIED WHILE ON MARQUIS.
  • Yup, all neurological deficits disappeared with meds & handwalking everyday for 3 mos.
  • QH mare developed EPM at 32, Very hard to watch because we could not save her but we did try
  • friends horse still in recovering phase
  • There were 2 on a farm I lived on that had it.
  • There are very few horses in this community
  • Mare was diagnosed almost a year ago, has been on treatment since, still ataxic, slowly improving
  • Diagnosed in 7/2000, treated with diaprim & SMZs. 95% recovery but cannot canter to the right.
  • He was my 30 year old endurance horse (still competing) and he came down with it quickly. Euthanize
  • EPM is wide spread here in North Texas and treatments very greatly.
  • This horse came from Wyoming. I don't know of any others in NW PA.
  • The horse relapsed twice, never regained full muscling
  • horse was fed equine Silverling Herbs for EPM and fully recovered, cost to owner was $200.00
  • After treatment he went back into training and died from a heart attack.
  • The EPM migrated to the brain of our good show horse and he had seizures.Recovered-still has seizure
  • I bought him at an auction as a rescue.
  • Along with tradtional tx, accupuncture and herbs have made a huge difference
  • One of my 6 horses developed clinical signs. Treated, relapsed, treated again, and has been stable.
  • EPM, and relapse, both triggered by long haul shipping Oh to FL, retired to pleasure horse riding.
  • One broodmare in the mid-90's who foaled and improved with treatment.
  • Mine and many others around me. My horse has permanent neurologic damage.
  • responded well to marquis. Back to work after 3 months.
  • I had never even heard of EPM. Need more info and education!
  • One recovered but it recurred two years later, one recovered completely
  • This has gone on for last 2+ yrs,she worries about riding him,not safe(?),still seems OK sometimes
  • TB yrling from KY. Ship to BC, Can. 6 weeks before symptoms. navigator and ? treatmnt. died.
  • I had a 3 year old TB colt come down with it and was put down.
  • the med Marquis is ineffective. boosting the immune system really helps. Tranfer Factor from 4 life
  • horse recovered after lengthy treatment. Still living at 30 yrs old today.
  • Mare had early symptoms and fully recovered.
  • One horse is still not rideable. Another was treated and has returned to endurance riding.
  • We have been lucky enough not to have seen it so far, and are very thankful.
  • yrs ago, friends horses, 90 % normal function returned
  • My horse tested low positive for EPM. His symptoms later proved to be stringhalt.
  • My RSW Champion stallion "got" EPM...I lost him after treating him but had 4 years..he sired a WC
  • I currently own a mare that was treated for EPM when young
  • my mare aquired a acute case of EPM and had to be put down 2 weeks later. it was horrible!
  • the horse was euthanized
  • 15 yr old Arabian gelding diagnosed at 4. No muscle atrophy, pasture sound. Unbalanced with rider.
  • Recovered, but was never the same...
  • I still have him; can't ride him any longer, epm rendered him unrideable, too risky
  • she was diagnosed back in late 90's & went on the 7mo meds. she was fine.
  • toby was a rescue horse who came to me with the it. he lived thanks to marquis.
  • yes, the mare recovered and is being used as a cutting horse in College level rodeo!
  • We treated the horse with oxytet & he recovered with no ill effects
  • 18 yrs ASH barren mare was just "off" for a year...vet did physical exam ...in ten minutes, he knew.
  • horse did not recover, relapsed and euthanized
  • a local rescue has dealt with many cases
  • My dressage mare was dx with EPM last Feb. With treatment she has recovered but takes miss steps
  • Our three dogs keep the opossums away.
  • my horse did not make it. put down after 6 months' treatment
  • He was 20yrs old. Hes 25 now. He has neurological damage. Hes doing well in retirement.
  • We caught it early, treated with Marquis and triads, thiamine, vitamin E, B12, full recovery
  • my Vet is into EPM research we used Marquis 1 month, duralactin, and stress packs
  • Horse was put down
  • I lost one horse to EPM and have one that we were able to treat and save but he is no longer ridable
  • We diagnosed EPM early. Treated with Navigator for 30 days. The mare made a full recovery.
  • My older gelding had it. I can ride him, but he is not as strong as before.
  • Our AQH contracted EPM 3 yrs ago. He was treated with Oxy and has recovered but is no longer rideab
  • My horse had EMP twice. The first treatment went well, but the second time we had to put him down.
  • a horse at barn we boarded at wasted away before owner used Marquis. It worked but tooo late for th
  • my friend's horse died as he was trailing him to Cornell for help with the disease
  • 4 friends horses at other farms all recovered, my 35 yr old stable but crooked
  • the horse did not recover
  • noticed gait variation, vet put horse on marquis, fully recovered, went on to win races and enduranc
  • she's being treated now with Marquis for 28 days...we hope we got it early enough
  • He was treated this summer and seems to be much better, haven't tried jumping yet
  • luckily a mild case, but her personality is probably permanently changed
  • My stallions show career was ended by it. A gelding showed it in pre sales check.
  • He was two when treated and recovered still has some tracing problems but keeps getting better.
  • I do not know the status of the horse the owners placed him for adoption through a rescue organizati
  • MY horse was put down, He laid down and could not get back up. Huntsville,Al
  • Never defnitively diagnosed but we treated as such. The horse was sold. It was a client horse boar
  • horse is in treatment and showing great improvement
  • Lost him after second time round with EMP .. ::((
  • Very rapid onset in a 23+ yr old QH. Recovered after intense drug regimen but left unsteady hindqtrs
  • We were able to identify epm very early and treat my 3 yo filly w/Marquis & Vit E & now healthy
  • Was back in the archaic days, even before the banana flavored stuff. Made a fully recovery though.
  • a client had a dressage horse diagnosed with it
  • We keep our horses healthy enough
  • Purchased yearling QH filly w/EPM she did not recover after Marquis treatment and is a companion.
  • 12 year old Arab gelding EPM in 1993 - 1998 Arabian Horse Assoc NATIONAL Competitive Trail CHAMPION
  • I am thankful that this is one thing that I don't have to worry about
  • Mare survived to be a trail horse but dressage career over.
  • Mixed - if caught early, appear to fully recover; less so if symptoms severe
  • Bayer drug Marqui affective, no laminitis problems
  • My horse teste positive for EPM, but has shown no symptoms yet.
  • Thankfully no, I haven't experienced this condition with any of my three horses.
  • We fought a year-long losing battle. :<(
  • After two months of treatment he recovered but not 100% only to find that he other spinal issues
  • After several treatments and relapses we had to put him down.
  • Thank God we haven't had to endure this nasty parasite!! God Bless those that have!
  • Yes, I lost my beloved 3YO Standardbred in 2001 to EPM. His mother had in as well.
  • No. Treated w/Marquis and navigator. did not recover
  • I had a mare in foal with EPM in 1990. The mare was treated aggressively,both mare & foal recovered.
  • In the last 30 years I have seen 75-100 cases of EPM, often the horse never recovered fully.
  • Several I have had have come back to different degrees of recovery.
  • 21 year old QH mare. Has trouble even holding a foot up for the farrier! They suspect stray cats!
  • it was a Tb filly at the track and we caught it early and treated. She came back approx 90%
  • horse never recovered, but died due to colic
  • Lost my Duke, April 24, 1997 to EPM
  • Started showing clinical signs 5/07,treated with 1 month Marquis, put down 9/07. Owner-Vet Tech.
  • I was told he would never be ridden again and he is as good as he was before. accupuncture helped
  • This horse has recovered thanks to VA Tech Equine Vet Team
  • Northeast Ohio area
  • I lost him to EPM.
  • My friends horse was diagnosed with
  • never the same again. should have put him down. he's miserable, even years later. real shame. too b
  • Yes, but not able to compete to thier full potential
  • In both cases the horses had to be euthanized
  • We lost a gelding to EPM in 2007. He had been on pasture with daily suppliments of grain since his
  • He was treated and has since been retired due to side effects from the EPM.
  • 7 yr old TB gelding - treated for 2 weeks at UC Davis, did not improve - euthanized
  • still treating my EPM case
  • My horse fully recovered after being treated for EPM. Wouldn't know she had it if you weren't told.
  • Progressed so rapidly tht vets did not think EPM. Horse died, confirmed EPM,i
  • Back in 1994,our old mare had EPM affecting cranial nerve,had to put her down.
  • My first horse died of the disease. My second horse recovered and then relapsed.
  • Riley has had some "hitcheyness" in his left hind but found a way to compensate
  • I HAVE NO PROBLEM KILLING POSSUMS. STOPPED FEEDING CAT FOOD OUTSIDE.
  • the horse died from complications of a fall during the acute phase of EPM
  • We got it just as it started. 2 month treament and totally gone!
  • I live in the White Mtns. of Az. and have not heard of any cases near me.
  • I have had two,1put down
  • Several were diagnosed quickly and survived. Others, were not so lucky. Shoot opossums!
  • One horse had to be put down and the other is permanently damaged.
  • fully recovered!!!
  • Yes, he has recovered.
  • My horse had a spinal tap at Auburn. U of K diagnosed her as positive for EPM. I gave drugs, No
  • My sister's Arab stallion has been diagnosed with EPM; he is in the early stage right now.
  • Sudden severe onset, it was nasty. Horse euthanatized.
  • ataxia
  • I was given "free" ex show horse he was diagnosed with EPM after $1,000 and time he recovered.
  • I had one that died, a friend has one now that seems like he will beat it.
  • My horse had to be put down in 1991. It all happened so fast and he did not respond to DSMO.
  • A clients 8 yr arabian stallion went down in the pasture, paralyzed, died 4 days later
  • several treatments with Marqesis (sp?), not fully recovered, poor px.
  • It was a horrible experience and both horses died.
  • 5yo Anglo treated successfully,now competes at prelim at age 15.
  • EPM epidemic at a barn that was becoming increasingly surrounded by housing development
  • 11 year healthy Morgan mare, until she got EPM. 2 bouts Marquis, 5 months, bad laminitis, put down
  • 1 horse fully recovered. anouther passed away because of it.
  • One on mine had EPM, also a friend's horse that we recognized the symptoms early and treated with su
  • eyelid drooped first, then bizarre respones to stimuli up to flippling over. Euthanized for safety.
  • She was started immediately on Marquis when she became symptomatic and is improving greatly.
  • I had a Standarbred mare that was misdiagnosed with EPM but it was a different problem
  • horse was euthanized
  • Have treated 2 of my 8 horses. 1 horse has made full recovery, Other horse has other problems also.
  • Sad, had to be put down. no idea where it came from.
  • The horse had to be put down.
  • no, it had to be put down
  • I know of 5 horses that have been euthanized due to EPM infection.
  • Still fighting the lasting results!
  • We have had a total of 3 horses that have contracted EPM, young gelding, older gelding, stallion.
  • Was diagnosed by 2 vet exams and confirmed by blood test. Horse is well now & competes in NBHA.
  • My horse was diagnosed with EPM Dec 2006, treated with Marquis and appears to be doing well.
  • Yearling filly.
  • No did not recover fully this was years ago
  • This horse recovered well enough to return to Endurance
  • The horse fully recovered with 90 days of treatement and rest.
  • 2 yo. A lot of improvement in 6 mo, but not over it yet.
  • The colt wasn't treated with marquis and had to be put to sleep.
  • Horse treated with Marquis (?), did not fully recover and was retired
  • 90% recovery but would never take again after three successive colts
  • My horse was (wrongly) diagnosed with EPM-she is fine today
  • Although 85% physically recovered, mentally only 50%
  • The elderly gelding suffered two bouts despite treatment but died of other causes.
  • The horse was successfully treated with no side affects.
  • not common in arizona
  • Not fully, my horse now has hind end coordination issues.
  • 1 recovered and 2 were euthanized
  • My horse was found to be moderately exposed. 6 month treatment, good as new
  • on the way to recovery
  • Actually I can answer yes to the first three choices; I lost a 35year old mare, there more w/S&S
  • May 07Warmblood, previously undiagnosed.Onset following relaxant injection.Still recovering
  • the horse did not recover
  • 95% recovered
  • Horse had trouble with left lead. Lameness exam found EPM - cured by Marquis.
  • I don't know of a single case in Alaska
  • i currently have a horse that just finnished up her meds for epm. i rode her last week
  • My friends horse was one of the first in 1986. She didn't make it, after many types of medication
  • I have had 2 horses that had EPM. One was a yearling filly and the other a yearling gelding
  • diagnosed 2 weeks ago, treating now, fingers crossed!
  • I own a horse with EPM, and know many others with EPM horses. It is very common in Michigan.
  • I've worked on a few race horses that had it
  • My horse has suffered with a chronic EPM infection for close to 4 years.
  • he had to be put down
  • My horse survived for 17 weeks with agressive treatment costing some $2000, but it finally won.

About the Author

Erin Ryder

Erin Ryder is a former news editor of The Horse: Your Guide To Equine Health Care.

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