Tetanus in dogs | PetMD

What is tetanus in dogs?

Tetanus in dogs is caused by a toxin produced by bacteria called Clostridium tetani. This toxin targets the central nervous system (such as the nerves, spinal cord, and brain) and causes muscle spasms and hyperactive behavior.

Dogs exposed to the bacteria through an open wound produce the toxin, usually through a deep puncture wound.

Tetanus spores are widespread in the environment and can survive for months or even years in the soil. These spores pose no problem if they are eaten or land on the skin. Instead, they cause infection when they burrow deep into the body, where there isn't enough oxygen.

In the body, the spores “wake up” and begin to produce a poison called tetanospasmin. This toxin will find the central nervous system, usually a nerve near the site of injury. From there, it travels up the nerve, reaching the spinal cord and eventually the brain.

Symptoms are possible wherever the toxin is present as it passes through the dog's body. Typically, signs of illness appear within 5 to 10 days after the sore appears, but they can appear as early as 3 days after exposure or as long as 3 weeks after the poison enters the system.

Symptoms of tetanus in dogs

Common signs of tetanus in dogs include:

• Muscle stiffness
• Tremors
• Difficulty walking
• Difficulty swallowing, eating or drinking
• Excessive drooling

There are two forms of tetanus in dogs: the localized form (which is the most common) and the generalized form.

In the localized form of the disease, signs develop mainly in the area closest to the wound. Muscles may become tense, stiff, and tremors may develop. Sometimes an entire leg may be affected.

The localized form of the disease can sometimes become a generalized form of the disease.

The generalized form of the disease is more serious and affects large areas of the body. These animals can walk in a very stiff manner, with their tail held straight or straight behind them.

If the muscles are so stiff that they cannot bend the legs, they will stand with all four legs rigidly extended, which is called the “saw horse” position.

Sometimes the area around the face and head is most seriously affected, with the animal holding its lips back in a “sinister smile” and its jaws tightly closed. For this reason, tetanus is often called tetanus.

Affected animals may be unable to swallow, leading to difficulty eating or drinking, as well as excessive drooling. If muscle spasms affect the throat or muscles that control breathing, respiratory distress may result. Because many muscles contract and generate heat, these dogs can develop a fever.

How Vets Diagnose Tetanus in Dogs

In most cases, veterinarians can diagnose tetanus based on the findings of a physical exam. This is a much simpler process if there is a sore to support the suspected diagnosis.

Although there are tests available to detect the toxin or C. tetani bacteria, these tests may be unreliable and are generally not recommended.

Your veterinarian can also perform basic screening tests to look for other potential problems, including blood tests, urinalysis and x-rays. Depending on the situation, other tests may be recommended.

Treatment of tetanus in dogs

If the disease is detected early, antitoxin treatment can reduce its severity. However, once the poison attaches to nerve cells, the antitoxin is no longer effective and may cause more side effects than benefits.

For most animals, antibiotics are appropriate. Antibiotics do not directly affect the toxin, but if the underlying bacteria can be killed, this will stop the release of additional toxin into the dog's system. This reduces the severity of the illness and allows the body to fight off any remaining toxins.

If your veterinarian discovers a wound, he or she will likely want to surgically debride or clean it. This includes removing all tissue in and around the wound to remove as much C. tetani bacteria as possible, which reduces the amount of toxins produced.

Dogs with tetanus require very intensive medical care. Often, they are placed on intravenous (IV) drips and medications for long periods of time. After surgery, if they are unable to eat on their own, they may need a feeding tube.

Most dogs require a lot of nursing care in a quiet, dark environment that reduces stimulation that can trigger muscle spasms. Medications can be used to try to reduce these spasms, but they have potential side effects and should be used with caution.

Recovery and Management of Tetanus in Dogs

Dogs with localized tetanus often recover with early treatment, while generalized tetanus carries a much more serious prognosis.

For localized tetanus, it may take a month or more for all signs to disappear. For dogs that are more severely affected or have the generalized form of the disease, survival rates are as low as 50%.

The sooner the diagnosis and the more aggressive the supportive care, the better the prognosis.

The best way to prevent tetanus in dogs is to monitor your dog for any new injuries and seek appropriate care immediately. Proper cleaning of the wound (often under sedation if the wound is deep) is important to eliminate any bacteria. Monitoring antibiotics for these deep wounds is also essential.

If your dog develops signs suggestive of tetanus, it is essential to report it to your veterinarian immediately. Prompt and appropriate treatment saves lives in cases of tetanus.