A Snotty Nose: Strangles or Not?

One day back in September, Daisy was standing out in the middle of the pasture when I came out for the morning chores and I could tell at a glance that something was wrong. Basically, she was drooping. Wilting. Like a plant deprived of water.

A closer look revealed that she also had a big fist-sized clot of snot in her nose. I didn’t need to take her temperature — I could tell she had one by her listless behavior. Instead, the first thing I checked to see was if there was a lump under her jaw.

My fear was Strangles — every horse owner’s nightmare whether they know it or not.

Strangles is caused by a bacteria, Streptococcus equi, which is similar to the bacteria which causes human strep throat. It’s highly contagious — so contagious that my vet swears that it can be spread by a contaminated horse trailer being pulled down the road.

The initial outbreak of strangles isn’t usually bad. One horse in your herd runs a temperature, feels crappy, gets a snotty nose, coughs, and then develops swelling under the jaw which, after anywhere from a few days to a couple of weeks, gets a hole in it that drains pus. After the pus drains, the horse feels better. Some cases are easy and over and done with in a matter of days.

However, strangles has the potential to be anything but simple. Strangles has an 8 percent mortality rate because it can spread to other areas of the body and cause Bastard Strangles, a condition which truly lives up to its name. Bastard strangles can cause asphyxia, heart disease, pneumonia, purpura haemorrhagica, or abscesses that rupture in another part of the body and kill the horse.

Contact with both the highly contagious snot and pus puts other horses at risk. If you have it on your farm, quarantine the farm immediately. If I were you, I’d vaccinate every horse on your place at the first sign of it, and the neighbors should vaccinate their horses, too.

My barn had an outbreak of strangles once and it was horrible. The disease came in on one new horse who had picked it up at a sales barn, but hadn’t come down with it during her 30-day quarantine period. Despite vaccinating every horse as quickly as possible, it still took about six months before the disease was off the farm. I couldn’t take any new boarders during that time and none of the horses could leave the premises. Three months after the last case, I thought I was out of danger. But then one day, a two-year old suddenly coliced. He died in the trailer on the way to the vet. The autopsy showed that bastard strangles had formed a football-sized abscess in his intestines and it had burst, killing him.

Considering strangles has an eight per cent mortality rate, I guess I was lucky to have only one in thirty die. Only I didn’t feel very lucky.

So when I saw Daisy standing there with a temperature, a cough, and a snotty nose, my first action was to call the vet for vaccinations for the others and penicillin for Daisy. I wasn’t positive it was strangles — Daisy had no swelling under her jaw — but she was one who had the disease when I had the outbreak in my barn — and the second time a horse gets strangles, the symptoms can be deceptively minor, though just as contagious.

The penicillin cleared Daisy’s snotty nose up after four days, and I saw no symptoms in any of the other horses. I couldn’t imagine where she could have gotten strangles from — none of the neighbor’s horses were new or sick. The two rescue horses we have, Charlie and Willow, had been on the farm since June and they had both been quarantined before that for over thirty days. Just when I decided it must have been some other upper respiratory infection —  Witch came in one day in early November with a temp and a snotty nose.

Witch had never had strangles before, but she had been vaccinated. She was otherwise very healthy, so I thought instead of giving her penicillin, I’d let the disease run its course. Sure enough, the progression through her symptoms was textbook strangles: fever, cough, and a snotty nose, followed by a small lump that abscessed fairly quickly. Thanks to the vaccination, though, all her symptoms were fairly mild, and she cleared up within two weeks.

And this time, I noticed a trace of snot in Willow’s nose, too.

Ah, hah!

I took Willow’s temperature. Slightly elevated. But after two days, the snotty nose disappeared along with the temperature.

And then, two weeks later, the snot was back. And then gone. And then back.

After questioning my vet, I found out that you can add another side-effect to the list of consequences of strangles: an infection of a horse’s gutteral pouches.

A horse’s gutteral pouches are sacs of air connected to the Eustachian tube below the ear, one on either side of the horse’s head.

According to my vet, the bacteria from strangles can infect the gutteral pouches turning the horse into a constant carrier of the disease. The gutteral pouch becomes filled with mucous which drains out the nasal passages. Horses that are infected usually don’t feel well and may display depression. Treatment includes antibiotics and flushing the gutteral pouch with a wash to remove the pus.

I went out to the pasture to have a talk with Willow. Yes, now that I knew what I was looking for, I could see that what I had interpreted as a rescue horse’s depression could also have a physical origin. And because the gutteral pouches are intertwined by cranial nerves, if a horse has inflammation in them, it can also affect a horse’s thoughts and learning.

But that didn’t prove Willow was a carrier of strangles. My vet explained that in order to know for sure, I’ll have to take a sample of her nasal discharge the next time it happens and we’ll have it tested at UC Davis.

Stay tuned, eh?