In early April 2022, strangles broke out at our facility in Sierning, Upper Austria. In this report, we would like to disclose the course of the disease and its consequences.

Course and symptoms

At the time of the outbreak, there were six horses at our facility – three of our own horses and three horses that were here for training.

First the disease broke out in three horses, two others followed. The horses were sick for 6 weeks and it took a total of three and a half months before all horses were no longer contagious.

The first three horses, Isa, Franz and Phoebe became severely ill. In the case of Phoebe, the disease eventually led to her death. The horses who fell ill later, Monty and Jupiter, had a moderate and a mild course of the disease. The gelding Cody did not get sick or had such a mild course that we could not detect any symptoms.

The severely ill horses suffered from purulent nasal discharge, high fever, coughing and foremost from swollen and bursting lymph nodes. The swelling can be thought of as 3 to 10 cm pus pimples that mature for 2-3 weeks and eventually burst. During this time, the fever is high, and the horses are unwell.

The bursting of the lymph nodes is a nasty business (even more pus in addition to that from the nose …), but it gives the horses great relief. The pressure is gone, the fever drops, and the horses behave more lively. After the bursting, it took more than three weeks for the pus to stop coming out and for the wounds to slowly close.

In the case of Isa and Phoebe, unfortunately, the bursting of the lymph nodes on the underside of the head was not enough!

Severe course with Isa

When the burst lymph nodes on the underside of Isa’s head began to heal, a lymph node between her head and neck filled up. This became the size of a fist and pressed on the trachea. Isa almost suffocated. (Emergency on Easter Monday in the middle of the night!).

It was not possible to cut open the lymph node before it was ripe, because there are many blood vessels running on the corresponding spot. It took two weeks for the node to mature and burst. After that it took another three weeks until no more pus came out and the wound (the hole!) started to close.

Fatal course with Phoebe

Phoebe apparently recovered twice during the course of the disease. She was the first to have the lymph nodes on the underside of her head burst, the first to have her fever go down, and the first to appear to be well again.

Two weeks later, Phoebe began to have a fever again and swelling appeared on her chest. The beacteria had migrated to the lymph node there. The lymph node is located further under the skin than the one on the head. After an ultrasound examination, the node was cut open. Pus came out as if a carton of milk had been poured out. Again, Phoebe apparently became healthy. The wound was irrigated twice a day, began to heal and the fever was gone.

However, a week later, Phoebe suddenly had trouble walking. She fell and could not stand up. She began to roll her eyes and gallop while lying on her side. Just before the vet arrived, she managed to jump up again.

However, all her legs failed! We supported her standing. It was diagnosed that strangles had become neurological. Swollen lymph nodes inside the body were pressing on nerve pathways.

A rectal exam was done. That’s when Phoebe reared up uncontrollably, flipped over backwards, landed on her head, and flailed. She could no longer control her body! We decided to put her out of her misery and put her to sleep.

Transmission

Strangles is a droplet infection. It can be transmitted from horse to horse through nasal secretions and pus. Humans can become carriers if there is discharge from the horse on their clothing or other equipment and another horse licks it.

Therefore, it is necessary for the human to wash and change clothes when in contact with other, healthy horses!

Risk of infection after recovery

If horses are symptom-free, they may still continue to be contagious. Residue in the guttural pouch can cause horses to remain contagious for up to 36 months!

We therefore urge that recovered horses ALWAYS be tested before moving to other barns!

For this purpose, nasopharyngeal swabs are usually taken and examined by PCR test. However, it is possible that no germ is “caught” in the nasopharyngeal swab, even though the horse is still positive. Therefore, these tests are done three times. Nevertheless, this procedure only gives an 80% certainty.

Isa, Monty and Jupiter at the equine clinic Tillysburg for endoscopy

We have therefore decided to do an endoscopic guttural pouch examination with flushing and sampling for all horses. This leads to considerably higher costs, but it increases the certainty of “catching” the bacteria if it is present.

And indeed: Isa was still positive 8 weeks after her recovery! She appeared perfectly healthy, but the guttural pouches were still filled with pus! Without the test Isa, who was with us for training, would have gone home and infected the whole barn there!

After another examination again 3 weeks later, Isa was finally negative. Also, all other horses were tested negative! So, all guest horses could go home to their owners. To be on the safe side, we also will disinfect our stable completely!

Workload, personal perception, and financial effort

The time while strangles was raging in our stable was surreal. The amount of work – even though we don’t have many horses – was large. Checking fevers several times a day, washing out wounds, cleaning noses, giving medications as needed, checking on the horses in the nights …

Above all, however, the concern for the welfare of the horses was overwhelming. The setbacks with Isa and Phoebe caused us great concern. After Phoebe’s death, we had difficulties trusting the sustainability of improvements in other horses for a long time.

Due to the severe course of events and the workload involved, Florian stopped his teaching activities completely for 6 weeks, which led to considerable financial losses.

In addition, horses that were in training with Florian could not go home after completing their training and no new horses could follow for three and a half months. This also hurt financially.

In addition, there were corresponding veterinary costs, with each horse owner paying for their own horse.

Conclusion

Dear all, please do not take strangles lightly!

Many horse people believe it is a good thing for young horses to have had the disease once. This is true in retrospect, as the risk of infection is then lower or milder symptoms can be expected in the event of an outbreak. However, we strongly advise against being less careful with young horses because of this. The course can also be very bad for them and possibly end badly!

Furthermore, please be careful if your horse has been in a stable with strangles. It can infect other horses – no matter if it has shown symptoms itself or not! You can’t see what’s in the guttural pouch from the outside!

Now we have made it and are very happy that this time is behind us. Phoebe left a gap. However, we are happy that the remaining horses are healthy and no longer contagious! We hope we were able to give you some insight with this article.

Kind regards

Family Oberparleiter
July 2022

Jupiter, Cody, Florian, Monty, Franz, Ana and Isa