Dr. Waqas Nawaz PMAS Arid Agriculture University Rawalpindi Pakistan

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“It is an acute, often fatal disease caused by bacteria Cl. Tetani commonly found in soil”
Synonymous:
 Lockjaw
Etiology:
 Clostridium tetani
Host Range:
 Animals
 Human
Infection most commonly occurs after an injury, but may also develop after surgical
operation. The bacteria produce the toxin tetanospasmin which affects the Central Nervous
System. Different animals have different level of susceptibility to this bacteria.
Clostridium tetani spores are also commonly found in the feces of domestic animals,
especially those of horses, and in soil contaminated by the feces. Clostridium tetani spores may
stay in soil for many years and are resistant to many standard disinfection processes, including
steam heat (100º C for 15 minutes).
Although all species of domestic animals are susceptible to tetanus, horses are most
sensitive to tetanus toxin. If the germ enters a deep wound and the wound closes too soon, the
horse may easily contract the infection through his blood stream. A horse that receives a bad
wound, particularly if there is known to be tetanus in the area, should at once receive the anti-
tetanus vaccine which will prevent the disease.
Clinical Signs:
The earliest symptom of tetanus is extreme sensitivity.
Within 10 to 14 days following injury, horses become increasingly nervous. They jump
violently on being touched. Some seem unwilling to be handled and may respond with
aggression.
Protrusion of the third eyelid, and stiff gait are the most common clinical signs
Spasms of the masseter muscles--muscles that bring the upper jaw and lower jaw
together--occur early in the disease which results in "lockjaw"
Loud noises, colic, and sweating usually appear at a later stage of the disease.

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Treatment:
 Treatment usually consists of administration of antibiotics, tranquilizers, tetanus toxoid,
and antitoxin.
Persistent treatment and much nursing care are needed. Affected horses need to be protected
from light and sound that can stimulate nervousness. Horses are placed in darkened areas and
their ears are plugged with cotton.
 Antitoxins, antibiotics and sedatives are usually administered for several weeks.
If the animal has been vaccinated prior to the injury, responds to the tranquilizers, the prognosis
is usually good.
Prevention:
Prevention is twofold. Unvaccinated horses usually receive tetanus antitoxin with 24
hours following injury or surgery. This provide temporary protection for 10 to 14 days. If healing
is not complete by that time, vaccination is repeated. No horse should live its life without being
immunized with tetanus toxoid which provides a very stable immunity. Annual boosters and
vaccinations following injury or surgery provide good protection against tetanus.
Most cases of tetanus ultimately results in death of the affected animals. If diagnosed
early, treatment is aimed as destroying the bacteria so that no more toxin is produced then
reducing the effects of the toxin that have already been produced.
Large doses of antibiotics usually penicillin are used in combination with tetanus
antitoxin. If horses are able to eat feed, they should be offered at a height, where it can easily be
reachable. IV fluid and Catheterization of the bladder may also be necessary.
In severe cases, recovery chances are poor and in such cases Euthanasia on main ground
is also appropriate.