Most people are aware of tetanus (“lockjaw”) either through having vaccinations at the health centre or perhaps if they own a horse which has to be vaccinated against the disease. Both humans and horses are genetically susceptible to tetanus and a particularly risky combination of events is when a gardener receives a wound whilst handling horse dung. The tetanus-producing organism (Clostridium tetani) is found naturally in soil and horse manure and can exist as spores for many years. Dogs and cats only rarely get tetanus. In fact most vets will only see one or two cases in their professional lifetime but once seen, never forgotten. Because of the years I spent in animal welfare practice with a high turnover of cases, I managed to see two dogs and two cats with the condition during a period of 37 years. Dogs get the condition much more seriously. The disease affects the nervous system by producing a toxin which causes all the muscles to eventually go into spasm so the dog becomes almost as rigid as a rocking horse and the muscles of the mouth are drawn back in what is known as a sardonic smile (risus sardonicus). Eating, drinking and even blinking become almost impossible and in dogs the condition is often fatal if intensive care is not administered early enough. [caption id="attachment_623" align="alignleft" width="270" caption="Amber showing her rigid hind leg."][/caption] Cats are a different proposition. The tetanus bacteria are often introduced from a wound or a fight and the muscle spasm is usually localised in a hind leg. Over a period of a few days the leg becomes completely rigid and can only be trailed behind the cat. Amber was a three year old cat who enjoyed going out at night. Inevitably she got involved in a few territorial fights on her travels. Her owner brought her in because she was obviously lame. [caption id="attachment_628" align="alignright" width="300" caption="Amber's wound, the source of the tetanus infection, with the other cat's tooth."][/caption] When I examined her, I found another cat’s canine tooth embedded in her back leg. This deep puncture had allowed the tetanus organisms to become established in her damaged muscle tissue and the toxin then affected the muscles of the whole leg. I started Amber on a combination of penicillin, a drug called metronidazole and diazepam to relax the muscles and reduce the discomfort for her. It took about a week for the treatment to start to work and then there was a gradual relaxation of the muscles. By three weeks after she had been diagnosed, there was no trace of stiffness. During all this time, Amber continued to eat well and was only inconvenienced by the lameness. After the first case I saw in a cat, I reported it to our professional journal, The Veterinary Record. A few people wrote to me to say that they had seen cases in the tropics where cats had been neutered in less than ideal surgical conditions and without the benefit of antibiotics. So while tetanus is a pretty rare occurrence in the cat and cannot be vaccinated against, perhaps this case will remind us that the potential for tetanus is always present in the environment and that we should make sure that our own tetanus vaccinations are boosted every ten years and that we get a dose of antitoxin whenever we have a contaminated puncture wound. Horse owners should consult their vet about keeping up booster vaccinations against tetanus. Intervals vary so ask your vet for advice. It is important to remember that the antitoxin given when a horse has treatment for a wound will only give up to three weeks protection if the horse has not been vaccinated against tetanus. If you are concerned about any health problems in your cat, please contact your vet or use our interactive Cat Symptom Guide to help you decide what to do next.