Long term lyme?

Former client horse contracted lyme a few months after leaving here (2019). Unfortunately the new BO kept convincing HO that horse was just lazy and/or soft footed, so it took a while to get a diagnoses. Horse got very skinny. HO found new barn. Horse recently developed a skin issue. It was soon after vaccinations, so they assumed a vaccine reaction, but he developed pus filled bumps and then started to get sores/loose hair under his leg pits and on his face. Vet thinks it could be lyme related.

For various reasons, HO is finding horse ownership in her new province stressful, and brought up sending him back to me to use in lessons - I told her to think about it for two weeks. I would love to have him though, assuming he isn’t going to be useless. Wondering what I should know about Lyme.

Lyme is an easy treatment most of the time. And the test is cheap. Just get him tested and treat if needed, he should be fine! Sometimes there’s lasting effects for long term (like years) untreated Lyme, but most of the time they’re back to normal pretty quick.

Around here, in the northeast of the U.S., lyme is all around us. My husband’s had it a couple of times, one of my dogs as well, and my previous horse had it several times.

In my horse’s case (and possibly in my husband’s case as well), the question was whether the horse was actually re-infected three different times or whether after the initial treatment, the bacteria that cause lyme had gone dormant and then re-activated for whatever reason at a later date. (Lyme bacteria are kind of the original sleeper cells).

There’s also a separate question of long-term effects of lyme disease even once the bacterial infection has been successfully treated. These effects can include arthritis-like joint pains, nerve damage, and in some cases (at least in people) heart damage. These long-term effects may be more likely if the disease has gone undiagnosed and untreated for a while. And because horses are stoic, they may not show significant signs of infection for a while and that tends to delay the diagnosis.

You (or the horse’s owner) should get the horse tested using the Cornell test, which is sensitive and more accurate than other tests. There’s information on it here:
Cornell test for Lyme disease

Then, if the horse has lyme, the horse should be aggressively treated for it. If lyme is not common in your area, your vet won’t know much about it, so it will be on you to really push the vet.

Good luck!


Where I live (Mid-Atlantic) tick-borne diseases are rampant. Doxycycline is the preferred treatment and we don’t wait for test results to get started on Doxy (same goes for people). My experience watching multiple horses go through this - if they start to improve after a week on Doxy, that’s your answer, and keep treating with Doxy.

Full disclaimer: I’m not a vet or a doctor. I’ve just dealt with Lyme and other tick-borne diseases in my horse, friends’ horses, as well as myself, family members, and friends.

Good luck! I’ve seen many horses bounce back after Lyme!

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Exactly this. If you treat and see improvement I wouldn’t have any concerns about taking the horse on. Lyme is very common in my part of PA as well.

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@Posting_Trot the horse was tested and treated for Lyme, but probably 4-6week after infection. It is NOT common where I live, but is where she moved to. His current symptoms seem more like allergies, but her vet said could be a lyme flare?

He would be an amazing lesson horse for me, so not worried about spending $$ on on going treatment, but it’s a long trip to get him here (3 days or so), and I don’t want to cause him harm. He did poorly going there too, but not sure why. So much so that the hauler changed their route to drop him off earlier than planned.