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Meningeal Worm & Alpacas

Should you be worried about Meningeal worm? Do you have: white tailed deer, snails and alpacas or llamas? If the answer is yes keep reading.

If you think your alpaca has meningeal worm stop reading and call your vet. Then come back and finish reading while you wait.

white alpaca laying down with text overlay meningeal worm infection

It’s only January and it’s been a rough year out in the barn. Thursday the 11th after work I went out to close up the barn but I was missing an alpaca. Fred was in the barn but George was no where to be found. Walking into the pasture it didn’t take long to see his fluffy white outline in the field.

He was laying down in the typical cush position but he didn’t get up when he saw me walking over. Even after I got right next to him and told him to get his butt out of the rain he didn’t move. His eyes seemed out of focus and even when I pushed on his butt he would. not. move.

I had to basically pick him up (he’s about 150 pounds) and half carry/half push him into the barn. I immediately knew what was going on and my heart dropped.

brown alpaca with newborn alpaca cria in red coat

This wasn’t my first brush with m-worm. A few years ago Fred and George had a baby, his name was Henry and he was a fuzzy ball of happiness.

I wasn’t blogging very much when he was born and I don’t think he’s ever even been mentioned here. Before he was a year old Henry started showing the signs of meningeal worm infection.

He was so little and even with immediate help from the vet he wasn’t able to pull though. The second worst day of my life was when he died. It’s been two years and I still can’t look at pictures without crying.

sick alpaca with little girl in black and white coat

Had I known how Henry would die I would have had him euthanized. If Fred or George had shown any signs of difficulty breathing I would have called the vet back out and had then euthanized too.

Luckily it never got to that point with them. There is a line between a merciful death and holding out for recovery. As the owners and caretakers of the animals it’s our jobs to draw those lines.

Back to 2018, I had the vet come out on Friday and she agreed that it was meningeal worm. I was given a pile of drugs and instructions for 5 days of treatment. Then you wait.

It’s be about two weeks and he’s completely back to normal. He was more or less better by Saturday. Of course Fred needed to get in on the action and she started showing symptoms on the 28th. Her treatment didn’t go nearly as neatly. I’ll be writing two posts about those experiences soon.

Meningeal Worm Introduction:

M-worm is a White Tailed Deer parasite that uses snails as it’s secondary host. Alpacas get infected when they eat those snails or even when they come into contact with the snail trails. I live in a very wet area with lots of deer.

It’s basically m-worm paradise here. The vet was telling me about a man a few towns over that lost 1/2 his herd to m-worm even though he was following the anti-parasitic protocol put out by Cornell.

meningeal worm infection treatment medication

I give Fred & George monthly shots but I stopped when the ground froze. Frozen ground, no snails, no worms, right? That would be a no. They’ll both be getting monthly shots of Ivermectin from now on. Old literature gives an Ivermectin worming schedule that skips the winter months, do not skip months.

The symptoms take around 45 days to appear, that’s why it’s surprisingly common to see break though infections in December-January even though the animals have been off pasture or at least away from snails for a while. Basically, you’re never safe, stay vigilant.

Meningeal Worm Prevention:

little girl feeding white and brown alpacas from black bowl

Based on where you live you may never have a problem with m-worm or you may be fighting a losing battle. If you are in an area where it’s a problem you absolutely need to keep up on a worming schedule.

If you aren’t sure talk to the local large animal vet, they’ll be able to help you out and figure out a preventative worming plan. You can buy Ivermectin at Tractor Supply by the vial and you’ll need needles and syringes to administer the shots.

You can also keep away the parasite vectors, white tailed deer and snails. I’m not in the position to afford deer fence around the property and I’m not willing to use chemicals to kill snails. I have read that ducks and guinea hens are great in the battle against snails. My duck population has dwindled and the last guinea hen got hit by the school bus.

My snail killer lineup needs to be rejuvenated and I’m still mulling over my options. I’m leaning toward the guinea fowl, they’re loud and annoying but I haven’t seen a tick since I brought them home and Lyme disease is no joke around here. My dog ended up with Lyme in April so they’re looking really good right now.

I’m also reminiscing about my Muscovy ducks and thinking it’s time for them to make a come back if I can find any locally this spring.

Meningeal Worm Symptoms:

M-worm affects the nervous system. The back legs are usually affected first. That’s why when George wouldn’t get up I started to get concerned. When I noticed his gait was stiff and he was standing against the wall I knew what I was dealing with. I don’t have any pictures, I wasn’t focused on anything but helping them get better.

Alpacas are very good at hiding illness. The best way to know something is wrong is to spend time with your animals. You can’t know when they start to act off if you don’t understand how they act when they’re healthy.

If an animal seems off keep an even closer eye on them. If they show signs of stiffness in the back legs when they walk or can’t get up call the vet asap. If you have drugs on hand start treatment.

Wednesday night George was slow getting to the barn, Fred was there to greet me at the gate but he was still outside. I wrote it off as enjoying the nice weather but looking back it was probably an early sign. Early treatment is of the utmost importance. When neurological damage is done, it’s done. That’s why it’s so important to catch this early and treat it aggressively.

Meningeal Worm Treatment

three syringes and one tube of oral horse wormer

The treatment for Meningeal worm is a 5 day course of Ivermectin,  Banamine (anti-inflammatory) and Dexamethasone (anti-inflammatory steroid) injections. Along with a double dose of Safe-Guard which is an oral wormer, also for 5 days.

The doses are based on weight, your vet will be able to help you out with that. You can buy both wormers over the counter at Tractor Supply. You will also need needles and syringes, I got those from my vet. Needles are hard to come by in New York state.

A side effect of the wormers is swelling so it’s important to also treat with anti-inflammatory medications. Both Banamine and Dexamethasone are prescription medications. You guessed it, talk to the vet. Buying a bottle is cheaper than getting individual doses.

I feel very fortunate that my second and third brush with meningeal worm has had positive outcomes. I spent a lot of time looking for information on meningeal worm and alpacas and I kept ending up on the same difficult to navigate forums where the information went completely over my head. I hope I have condensed my knowledge of m-worm in a readable way.

I’m in the process of writing up the individual stories for George and Fred because they were very, very different. Symptoms are based on where the worms are and that can make a huge difference in how the infection appears between animals.

You can read more about my alpacas here:

Find out what our two pet alpacas do on our small farm

Rick Borden

Tuesday 20th of February 2024

My wife and I are right now dealing with it in our girl named Pie. It's been 10 days and she still can't use her back legs much. We rigged a sling with a come along for the first 5 days and now I help her stand but she can't stand up by herself. Her spirits are good and she us still feisty with the others ( which she always was) so that's good. This was a good article and I appreciate the info, thank you.


Wednesday 21st of February 2024

I'm so sorry that you're going through this. My girl Fred still has hind leg weakness years after surviving her Meningeal worm infection, if she gets going too quickly she ends up spinning in a circle. I hope Pie gets better soon

Annie Bruetsch

Monday 12th of August 2019

Thanks great words of wisdom! So difficult to watch and treat

Spring Mills Alpacas

cindi Kent

Monday 13th of May 2019

We have an alpaca that had the apparent m-worm symptoms this last winter, however we did not have any knowledge of the m-worm ....we had a vet out to check him out...she was supposed to be a known alpaca-vet in our we did not know the symptoms of this infestation, we were convinced that he had an accident of falling on the ice and injured his back...the vet gave injections of steroids and after a couple of weeks he got up on his own and we thought he was on his way to recovery...sadly yesterday while our shearer saw him and heard the story he informed us of the question is....after a few months of his symptoms, is he in pain? can we baby him and comfort him now with any medications...we truly love this guy..but don't want to keep him going if he is in pain....any hope?


Tuesday 7th of May 2019

I will love to see if you can send me a pic of the bottles of the medicine, I dont have a near by vet and definitely not one that come to my place :'( I will love to show them what they prescribed for our alpacas to see if they can do the same for mine, please?


Tuesday 7th of May 2019

I am sorry for your alpacas!!!

Debby Buben

Monday 11th of February 2019

I believe one of my older boys has M-Worm symptoms. He's still getting up and he's eating, but he is drooping his head and neck and is resting on the ground with his neck stretched out in front of him. He seems depressed, out of it, and like he has a headache. His back legs are still working and he does walk around some, but not like normal. He's always laying down with his head stretched out. There is field next to that corral where I know the deer have come through at night. And we had a lot of moisture this fall. I started him on Ivermectin and Panacure, and Banamine this weekend. If it's not M-worm, will this hurt him? I emailed my vet. Waiting to her back. Thank you for your article. It may have saved Dakota's life. He's 21 years old this year and I just love him.


Sunday 20th of October 2019

Hi Debbie, One of my males is doing exactly the same thing with stretching his neck out and laying down all the time. Seems to have a normal appetite and lately has been spending more time in our pastures. He has been treated monthly with ivermectin injections since July 2019. Vet came out took blood cane back normal and I stated treating him for possibly stomach ulcers. 20 days of daily dosage and he did seem to be more social. Tonight they all got there monthly ivermectin and he literally collapsed within 20 sec after administering and was down for about 8min. He did get back up but he has exactly the same symptoms you described. Depression I feel, lethargic, hanging head and stretched out neck with head on floor. Did you ever figure out what was wrong with your boy? I did treatment him with banamin before vet came out (3 days) but apparatus that can cause more aggravation if in fact he has ulcers. Also allowing me to “capture” him with no chase at all was my first sign of concern. Any feedback is much appreciated.


Wednesday 13th of February 2019

It doesn't sound like meningeal worm to me but the ivermectin and safeguard shouldn't hurt him. I'm sorry your boy isn't doing well, it's so hard when you don't know what's wrong, I hope your vet can help you.