A: Unlike humans, dogs and other carnivores have natural resistance to tetanus and are very rarely infected.

Although untreated, tetanus is a fatal neurologic disease, there does not appear to be a need to develop a vaccine for dogs since infection is so uncommon.

Horses and other farm animals do need routine tetanus toxoid injections as they are much more susceptible to this infection. The tetanus bacteria Clostridium tetani are present in soil and enter the body through a puncture wound that hasn't been cleaned properly. Within one or two weeks, the organisms produce toxins that travel from nerves in the area of the wound to the brain and spinal cord causing disruption of the normal conduction of nerve impulses.

Signs of tetanus in a dog would involve overstimulation of the nervous system. These may include muscle spasms in the body and tightening of the muscles of the face especially noticed around the ears and lips. Dogs with normally droopy ears may have more erect ears. Blinking is not possible, so the third eyelids are elevated to moisten and protect the eyes.

The expression "lockjaw" refers to tightness in the muscles controlling jaw movement. With progression of the disease the dog will have a very stiff gait and may have trouble breathing and swallowing. The symptoms get worse with any outside noise or stimulation.

Medical treatment includes antibiotic and tetanus antitoxin injections along with supportive hospital care. The prognosis is best if the symptoms were slow in onset and if treatment is begun early in the course of the disease.

At this time, we do not have a good laboratory test for tetanus is dogs, so treatment is begun when the presumptive diagnosis is made based on symptoms and the presence of a wound, if noted. Treatment is generally successful if begun early.

Several antibiotics are effective against, and in some cases a tetanus antitoxin is used. Supportive care to assist with breathing, hydration, feeding, and sedation to reduce muscle spasms is often needed for several weeks until the toxin has been eliminated from the body.

Dr. Francine K. Rattner is a veterinarian at South Arundel Veterinary Hospital in Edgewater. Please send questions to info@southarundelvet.com.