Alternative treatment for Neck Threadworm issues?

[JB]

I was looking up some information about the nuchal ligament for another thread, and ran across this as a by-product of that.

The treatment is the same as that for Leptospira-associated uveitis. After the inflammation has subsided, ivermectin 0.2 mg/kg may be administered systemically. A single dose of ivermectin 0.2 mg/kg was found to be very effective in eliminating microfilariae from the skin of horses afflicted with dermatitis due to O. cervicalis. Alternatively, diethylcarbamazine 4 mg/kg daily is administered in the food for 21 days. At the first sign of recurrent inflammation during treatment, corticosteroid therapy is begun. In endemic areas prophylactic feeding of diethylcarbamazine and aspirin is recommended throughout the season when vectors are present. Aspirin may also be used continuously. The routine use of ivermectin and other highly effective anthelmintics appears to have substantially reduced the incidence of onchocercal uveitis in the United States.

It’s the right side of this link
https://www.sciencedirect.com/topics/veterinary-science-and-veterinary-medicine/nuchal-ligament

I don’t know what diethylcarbamazine is as a brand, but did find reference to Hetrazan. Maybe it’s an old product that isn’t around anymore? That’s not what really caught my attention though

It’s the aspirin.

That segment (I can’t access the full article) says that aspirin can be used continuously to help with microfilariae-induced uveitis, but could it also help with the body itching issues?

My vet will be coming soon for shots, so I’ll definitely ask her about that.

[xeroxchick]

I am no help in this at all but wth, threadworms?!! What is that? In the neck? WTF?

[JB]

:lol: :lol: :lol: :lol:

Yes, Neck Threadworms. Evil beasts. Adults cannot be killed, and live 10+ years :eek: :mad:

Juveniles are typically easily killed with ivermectin/moxidectin. But imagine if you end up with a horse who was not properly dewormed at some point in his life, and he’s got a build-up of adults :uhoh: He will regularly have a colony of juvies.

Fortunately, most horses are ok with that.

It’s the speshul horses who develop an allergy/sensitivity to them, and there’s a really, really, reeealllly long thread on that here somewhere.

But yes, these guys can and do migrate to the eye:eek::dead:

[Bluey]

Interesting, thank you.

[XTina]

Thank you JB and others that helped me diagnose Neck threadworms in my horse. It was confirmed by Vet and also by the obvious welts after Ivermectin. My horse is over seas in a remote area. She needed several treatments last summer.
This year I am wondering if she needs to also be treated with Moxidectin (for fear of encysted red worm erupting). She did well last year with treatment with no side effects. Does that mean she is safe to treat again this year with only Ivermectin? The product Quest is not available overseas but I could order online. If I need to use Quest how close can it be used to Ivermectin treatment? I understand that Moxidectin is much stronger and can not be double dosed. I will also be eager to hear about the aspirin. I appreciate the information I have received from this site and any other new information.

[Marla_100]

[QUOTE=JB;n10087138]
I was looking up some information about the nuchal ligament for another thread, and ran across this as a by-product of that.

It’s the aspirin.

That segment (I can’t access the full article) says that aspirin can be used continuously to help with microfilariae-induced uveitis, but could it also help with the body itching issues?

Re: Aspirin- I’ve read that itching is a very mild form of pain. Aspirin would, IMO, help alleviate that plus as an

anti-inflammatory, might help w/ that. Uveitus can be extremely painful so I can see why aspirin would help.

[Larbear]

@JB

It’s the aspirin.

That segment (I can’t access the full article) says that aspirin can be used continuously to help with microfilariae-induced uveitis, but could it also help with the body itching issues?

My vet will be coming soon for shots, so I’ll definitely ask her about that.

I think diethylcarbamazine is still around, it inhibits the metabolism of arachidonic acid in the microfilaria and makes them susceptible to attack by the immune system.

I don’t think asprin would do a whole lot for itching but aspirin also inhibits the metabolism of arachidonic acid and as posted previously, it would be helpful for pain for the uveitus.

[ayrabz]

really wish a vet would weigh in on this…as I think its quite misleading as written. I believe you’re discussing treating the midges stages. I would LOVE to know if ‘Adult Neck Thread worm’ CAN? be diagnosed? I have long suspected my older gelding once beginning intermittent lameness and some neck injections (and every other limb reviewed as the lameness would move) and then a thickening crest along the ligament (however…no extra body fat/weight anywhere, no other indicators…) and then? finally along that ligament area: total mane loss. no itching. none. no rubbing. no dandruff/scab scruffing. just no hair after about 4 inches from forelock to just before withers. anyway. nothing you can do? if that adult (s) worm is in there from what I have been instructed or researched. so you’re treating the itching and the midges stages right? Because IF there is a treatment for the adult worm I would LOVE to know it!

[JB]

Thanks to those who weighed in on the mechanism of aspirin and diethylcarbamazine - makes a lot of sense.

@ayrabz

really wish a vet would weigh in on this…as I think its quite misleading as written.

It’s a summary, and I can’t access the full article

I believe you’re discussing treating the midges stages.

Yes, because we currently don’t have anything that kills the adults

I would LOVE to know if ‘Adult Neck Thread worm’ CAN? be diagnosed?

If nothing else, via the presence of the microfilariae, which can definitely be seen in the eye of horses affected that way, and can be “diagnosed” via symptom worsening and then improving with treatment

It can also be diagnosed with a biopsy (or necropsy), as there was a case I found several years ago about a horse who was put down due to suspected Wobblers, an necropsy showed the nuchal ligament adversely affected by Onchocerca, aka NTW

I have long suspected my older gelding once beginning intermittent lameness and some neck injections (and every other limb reviewed as the lameness would move) and then a thickening crest along the ligament (however…no extra body fat/weight anywhere, no other indicators…) and then? finally along that ligament area: total mane loss. no itching. none. no rubbing. no dandruff/scab scruffing. just no hair after about 4 inches from forelock to just before withers. anyway. nothing you can do? if that adult (s) worm is in there from what I have been instructed or researched. so you’re treating the itching and the midges stages right? Because IF there is a treatment for the adult worm I would LOVE to know it!

No treatment for the adults Treatment for the microfilariae is some protocol of single or, in many cases, double dosing ivermectin or Equimax (no idea why the added praziquantel is what some horses need), every 2 weeks, and no, I don’t know why mots horses seem to need a double dose, at least to start

[XTina]

In regards to the Aspirin is it a special type for horses? What strength would a 800 lb horse need?
Would anyone have information regarding the need to treat first with Moxidectin for Onchocerca Microfilariae?

[JB]

@XTina

In regards to the Aspirin is it a special type for horses? What strength would a 800 lb horse need?

I’m not up to speed on aspirin dosing for horses, but it would be easy to research

Would anyone have information regarding the need to treat first with Moxidectin for Onchocerca Microfilariae?

Both ivermectin and moxidectin kill the microfilariae. I honestly can’t tell you why many horses seem to need bi-weekly treatments of not just ivermectin, not just double ivermectin, but double Equimax. Certainly not all. But as seen in that insanely long “original” thread on NTWs, and from my (granted, anecdotal) experiences with many more people and their horses since them, double Equimax seems to be the key, at least to getting the horses started with relief.

All that is to say - I don’t personally know of anyone who has started the treatment protocol with Quest, at least not intentionally. Most people I personally know, and “know” who have gone through this, use Quest Plus in the March-May timeframe anyway (based on location) as the “ideal” Spring treatment, which is before midge/noseeum season. They then start the Equimax protocol roughly 6-8 weeks later, which is not ideal but still pretty safe.

[XTina]

Thank you JB so much for your reply. I will look further into the aspirin use. If this summer she is having a terrible time again I am hoping the aspirin might do some good. She unfortunately did need 2 double dosing of Equimax followed later by a single. There was some mention in the original thread about the use of Moxidectin prior to the Ivermectin in case of a build up of encycted small worms that might be forced into erupting all at once. Saying that only Moxidectin or Panacur eliminate the “encysted” worms. Thankfully she did not have any problem last summer with treatment. I think that the problem is with rescue horses that might have an overload of worms. If I have to wait 6-8 weeks before I can use Equimax that might be to late for her. She started symptoms last year at the end of May ( the mare is in Greece). I can’t tell you enough how grateful I am for the information in this forum. Because of it I was able to help her and she is a sweet mare even when she was itching like crazy.

[JB]

@XTina

There was some mention in the original thread about the use of Moxidectin prior to the Ivermectin in case of a build up of encycted small worms that might be forced into erupting all at once.

It is certainly possible, and has definitely happened, that a horse with both a moderate or high count of adult strongyles and a large enough encysted strongyle colony, could end up with the encysted larva emerging once the adults are cleaned out. “House is clean, ready to party!”.

For horses with a regular clean FEC, the odds of that are almost none.

It doesn’t affect the NTW issue in either case. But, given that Spring is the ideal time for Quest Plus anyway, that’s usually the best place to start the year off.

Saying that only Moxidectin or Panacur eliminate the “encysted” worms.

Just for clarification - moxidectin (for which Quest and Quest Plus are the only brands in the US), and a 5-consecutive double dose of fenbendazole (for which Panacur and Safeguard are 2 brands), are indeed all that will kill encysted strongyle larval

I’m so glad this has helped your mare!