Neurological reaction to vaccine?

[4horses]

My friend’s horse had a very scary reaction to her vaccine for EWT and West Nile. She was having noisy breathing, standing abnormally, couldn’t clamp her tail, and running a 104 fever. She was having stiffness in her neck and couldn’t bend her neck/turn her head but had no swelling at the injection site.

She was vaccinated on Monday. On Wednesday she was slightly depressed and not quite right. By Thursday she was very sick. The vet came out and was there for a couple hours. The vet thought it might be West Nile or possibly herpes virus encephalitis and ran a couple tests as she thought it was neurological. They have had one case of EPM on that property but the vet didn’t think this could be EPM because of the fever.

They gave the mare banamine and dexamethasone and she has been improving since then. If this was something more serious I would have expected her to go downhill.

My friend is a bit nervous about ever vaccinating her mare again after this. All our horses were vaccinated by the same batch of vaccines and no one else had any issues. It just seems really odd. The mare had a minor reaction to her vaccines last year but nothing like this.

[carman_liz]

How old is this mare? How long has your friend had her, asking because I would wonder if she has ever been vaccinated with the same vaccine before in her life?(sorry just saw she had a smaller reaction last yr!!)

Is it at all possible the needle nicked something and she has a small infection going on from the injection site? Can the vet run some sort of allergy test on her to see if it was a true allergic reaction to the vaccine?

Not the same thing and maybe it takes longer with vaccs to see a reaction, but my mare was allergic to banamine. The few times she was sick in the 20+yrs I had her she had never been given banamine before. Ace, bute, all the vaccs, never banamine.

Within 15 min of the shot, given iv by the vet, her neck broke out in hives and was swollen, she was rubbing it on everything n everyone, on top of colicking as it was…one shot of dex and about 30 min later she was ok though. We thought it was a one time weird thing but she got sick again and a friend came out and did the iv injection for me, and she is a seasoned pro at shots, same reaction… After that I made sure it was on her record with the vet and never, ever tried it again. It just seems odd it took 2 days for the real onset of serious symptoms even though no other horses had adverse reactions.

What was the smaller reaction last yr, any of the same symptoms? I know after having your first child, most of the time our bodies react sooner with the second pregnancy as far as making your breasts ache, morning sickness, the general ahh…my body knows and is telling me I’m pregnant even before peeing on the stick thing. Usually labor is faster and smoother too since your body knows to start to dialate, muscle memory to push and technically expel the baby…ask me what I think about docs treating the labor ward like a factory line and inducing new moms just because they can when their body doesn’t have that first experience…sidenote…don’t ask me…lol.

Disclaimer yes this is a total generalization, I know everyone’s bodys are different though. But it is like the mamallaian body goes wait…what is this different thing going on or put into me…ahh I recognize it…and already know what to do about it, lets do it faster and better since I have experienced this before!!! Maybe that type of natural, instinctual response to react sooner each time applies to allergy causing substances in mammals as well?

Just my limited experience with a horse being allergic to an injected med and my totally not professional train of thought on the severity this time around vs last year, maybe others will chime in with similair situations with longer reaction times and better advice. Either way good luck and I am really glad she is getting better!

[starsandsun]

I went through a period where when my horse was vaccinated he would colic 24-48 hours later. It was like clockwork.

I have had blood pulled and titered to understand antibodies and we have a plan to only vaccinate for anything that’s low (or kill-able, like rabies - we will always vaccinate for that).

BTW, his worst colic was after the Potomac Horse Fever vaccine, at least in terms of presentation. That was a very quick colic after vaccination.

And, when we ran the titer about 6 weeks later, there was no evidence of PHFV in his blood. It was like it all burned off. And apparently that is a problem with that vaccine - it doesn’t last.

[trubandloki]

@4horses

My friend’s horse had a very scary reaction to her vaccine for EWT and West Nile. She was having noisy breathing, standing abnormally, couldn’t clamp her tail, and running a 104 fever. She was having stiffness in her neck and couldn’t bend her neck/turn her head but had no swelling at the injection site.

She was vaccinated on Monday. On Wednesday she was slightly depressed and not quite right. By Thursday she was very sick. The vet came out and was there for a couple hours. The vet thought it might be West Nile or possibly herpes virus encephalitis and ran a couple tests as she thought it was neurological. They have had one case of EPM on that property but the vet didn’t think this could be EPM because of the fever.

They gave the mare banamine and dexamethasone and she has been improving since then. If this was something more serious I would have expected her to go downhill.

My friend is a bit nervous about ever vaccinating her mare again after this. All our horses were vaccinated by the same batch of vaccines and no one else had any issues. It just seems really odd. The mare had a minor reaction to her vaccines last year but nothing like this.

With the symptoms showing as you say (very sick on Thursday), I would guess that something else is going on, other than a vaccine reaction and the timing is a coincidence.

I am confused why you would have expected the horse to go downhill after the treatment if it was something other than a vaccine reaction?

That aside, if your friend is worried about vaccine reactions then it is something to talk to the vet about and the vet and your friend can work out a vaccinating protocol that takes that into account.

Jingles for your friend’s horse.

[AnastasiaBeaverhousen]

How old is the mare?
My friend had an aged horse. She got the vaccine es that she could buy and gave them herself. She spaced them out so he didn’t have them all at once.

She did have the vet out to give him his rabies shot and any other that only a vet can give.

[NaturallyHappy]

It is my understanding vets report vaccine reactions to the manufacturer…perhaps her vet can use a different manufacturer in the future. We’ve done that before.

[4horses]

My attempt to Google neurological reaction to vaccines only gave me information on neurological reactions to COVID vaccinations in people. So it is possible but a rare side effect.

The mare seems to be doing better. It definitely was an odd reaction. I’m betting it could be some sort of allergy, or delayed allergic reaction as she was having noisy breathing but her lungs were clear.

[Marla_100]

find out the brand or manufacturer of the vaccine, then tell vet not to use this one again on this horse. One horse I had was OK with Merck vaccines stretched out singly.

[J-Lu]

My good friend and BO has an around 13 yr old mustang Mare that has had neurological symptoms to vaccines. They’ve had this mare for a good 7 years but never noticed it before ~2 years ago. She was wobbly on her feet, very not-quite-right in the pasture and the owner called the vet out immediately who treated her.

Of note, they used another vet and then switched to mine about 2-3 years ago. Maybe the brand of vaccine is different, maybe not. I don’t know.

They spaced the vaccines out last year and it seemed to help. We just had vaccines a few days ago and I was there when they discussed the vaccine plan for this horse. Our vet is only giving essential vaccines to this horse. They are spacing out rabies over the years and just giving vaccines that are known to be problematic in our area. Not vaccinating for anything not critical (I can’t remember what they are vaccinating for and not vaccinating for). I asked about the horse and our vet said she really never saw anything like the symptoms this mare developed.

Like I said, I know the mare was fully vaccinated in the past but she seems to have developed a scary neurological response to vaccines in the last 2-3 years. I have NO idea if it is related but this mare is on a path to insulin resistance and the vet and owner are now carefully managing her diet because the vet thinks the mare WILL founder eventually if it is not carefully managed.

Good luck with your horse!