Tetanus

Tetanus or ‘lockjaw’ is an acute, usually fatal disease caused by a bacterium Clostridium tetani found in soil. Infection occurs via a wound or after surgery, when the bacteria invade and produce a toxin called tetanospasmin which damages the nervous system. Deep puncture wounds and foot abscesses are particularly at risk of invasion by the bacteria. Horses are very susceptible to the disease and the spores can live in the soil for many years.

Clinical Signs:

Symptoms develop seven to twenty one days after exposure to the bacteria.

The first sign is the horse becoming extremely sensitive and nervous, reacting violently to movement and touch. A stiff gait and muscle spasms will develop.

Protrusion of the third eyelid is seen when the head is elevated or in response to being startled.

A raised tail head can be present. In more advanced cases, spasm in the muscles of the jaw and neck can prevent eating, drinking and swallowing – hence the name ‘lockjaw’.

In the later stages of the disease horses are unable to get up and suffer from fits. They eventually die from respiratory and heart failure.

Prevention

Is far better than cure; tetanus is a killer and totally preventable; vaccination is inexpensive and extremely effective; if at all unsure of tetanus vaccination status a dose of antitoxin should be given to any horse which sustains a wound; there is no excuse for any horse not to have tetanus vaccination cover.

Tetanus vaccination is inexpensive and extremely effective. A tetanus vaccination course involves two injections a few weeks apart followed by boosters every two to three years. Clean all wounds thoroughly, especially if deep. Unvaccinated horses or those with lapsed vaccinations must receive immediate veterinary treatment for all wounds, foot and dental infections in order that a dose of tetanus antitoxin can be given.

Treatment

Treatment must be early and aggressive to have any chance of success. Milder cases can occasionally be successfully treated but more severe cases are usually fatal. Treatment includes sedatives, antibiotics and tetanus antitoxin in large volumes. All cases must be kept in a quiet environment and need intensive nursing care.