What is Tetanus?
Horses are susceptible to tetanus, which is a very serious and often fatal disease caused by the bacteria Clostridium tetani which horses are particularly sensitive to. Clostridium tetani, is present as spores in the soil but is also found in the faeces and intestinal tract of horses and humans.
How does a horse get Tetanus?
Horses commonly acquire wounds that allow the Clostridium tetani bacterial spores to enter their system through contaminated soil. The wound that allows the spores to enter can be so small that it may not be noticed. Common wounds that put a horse at risk of tetanus include puncture wounds (particularly of the hoof), surgical wounds like castration incisions, open lacerations, crushing injuries, bone fractures and through the umbilical cord of foals.
Once the spores enter the wound if the aerobic conditions are favourable with the absence of oxygen and the presence of damaged/dead tissue, the bacteria continues to multiply causing a toxin to be produced. This toxin is a neurotoxin which blocks neurotransmissions causing muscle contractions and spasms known as tetany.
Signs
The signs of tetanus typically show 9-10 days after infection but can begin anywhere from 7 days to several weeks after infection. The toxin that is produced by the tetani spores causes muscle contractions with the first signs being a change in a horse’s movement or resting position. An affected horse will continue to have progressing muscle stiffness with signs including a stiffened gait, the tail becoming stiff and standing straight out, the ears stand erect/pricked, facial muscles become stiff causing lockjaw and the third eyelid goes into spasm and prolapses. As the condition progresses the horse will go down, have convulsions, go into respiratory failure and die a painful death.
Treatment
Treatment of tetanus is difficult and the majority of horses will end up dying or being euthanized due to the condition. If a tetanus diagnosis is made in the early stages a veterinarian may begin very intensive treatment involving administration of tetanus antitoxin, sedatives, muscle relaxants and antibiotics as well as thorough cleaning of the wound and removal of necrotic tissues. If a horse survives the first few days a complete recovery can take weeks, even months and other secondary infections or complications such as laminitis, colic, pneumonia and other infections can occur.
Prevention
Thankfully tetanus can be prevented with tetanus vaccinations. It is absolutely essential that all horses are kept up to date with their tetanus vaccinations. Speak to your veterinarian to discuss the best vaccination program for your horse.
Can people catch Tetanus from a horse?
Although tetanus can not be directly transmitted from horse to horse or horse to human the bacterial spores can survive for a long time in the soil. For this reason it is important that horse owners are also vaccinated for tetanus and have wounds seen by a doctor for correct treatment and advice in preventing a tetanus infection.
If you ever suspect your horse is suffering from tetanus contact your veterinary immediately.