Tetanus

Disease Overview

Tetanus is an often-fatal disease caused by the toxin produced by the anaerobic, spore-forming bacterium Clostridium tetani. C. tetani organisms are abundant in soil, making infection an ever-present risk.

Merck Animal Health Solutions

PRESTIGE® 5 + WNV

PRESTIGE® 5

PRESTIGE® 4

PRESTIGE® 3 + WNV

PRESTIGE® 3

Transmission

Infection usually occurs via a puncture wound (especially in the foot or muscle), laceration, surgical incision, or exposed tissue such as a foal’s umbilicus or postpartum mare’s reproductive tract (especially in the case of trauma or retained placenta).

Clinical Signs

Localized stiffness proceeding to general stiffness
Muscle spasms
Difficulty chewing (hence the common name “lockjaw”)
Erect ears; stiff, extended tail; dilated nostrils; prolapsed third eyelid
Difficulty walking, turning and backing
Extension of head and neck
Stiff leg muscles causing “sawhorse” stance
Sweating
Increased heart rate
Rapid breathing
Mucous membrane congestion
Temperature slightly above normal

Risk Factors

Because the tetanus bacterium is so common in the environment, all horses are at risk.

References

“Tetanus,” American Association of Equine Practitioners, accessed July 15, 2021,
aaep.org/guidelines/vaccination-guidelines/core-vaccination-guidelines/tetanus.
Henry R. Stämpfli, “Tetanus in Animals,” Merck Veterinary Manual, July 2021,
https://www.merckvetmanual.com/generalized-conditions/clostridial-diseases/tetanus-in-animals