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Home , Tetanus

Tetanus 237 feasible, immediate removal to a new farm, and removing the carcasses from pasture; promipt disposal of the car- the premises to a rendering plant. casses of dead animals by complete burning or deep burial in quicklime; CD. STEIN, a graduate of the University burning manure, bedding, and other of Pennsylvania, is a veterinarian in the contaminated material; thorough Animal Disease and Parasite Research Branch cleansing of contaminated stables, of the Agricultural Research Service. He followed by disinfection wdth a 5-per- has been with the Department of Agriculture cent solution of lye; and restrictions since igii. For many years he has done re- against skinning dead animals, feeding search on , equine infectious anemia, the carcasses to other animals on the and other infectious diseases of livestock.

Tetanus

C. D. STEIN

TETANUS, com.monly called lock- from which the air is excluded. Deep jaw, is a wound disease that punctured or lacerated wounds con- is usually accompanied by a fatal tox- taminated with foreign material or emia. The toxemia causes contrac- soil—such as may result from nail or tions of the voluntary muscles, mainly splinter punctures, fractured bones, those of the face, neck, body, legs, and gunshot wounds, castration, and har- tail. are the result of steady ness and saddle galls—therefore are and prolonged contractions of the more apt to produce tetanus than affected muscles. superficial open wounds. Tetanus is caused by a rod-shaped The disease occurs all over the germ, tetani, which produces world. It is most common in old farm- an extremely potent . The germs ing areas, especially in sections where form highly resistant, large terminal truck gardens, heavily manured land, spores, which give the organism a and swamps are contaminated with peculiar drumstick appearance. The tetanus germs. The organisms or their tetanus germs and spores remain lo- spores are scattered in the top layers calized at the place of the wound of soil and in street dust and hay. They where they enter the body. They often are in manure. multiply and produce the powerful The disease is common in people and toxin. The is absorbed and horses. It may attack other warm- carried by the blood to all parts of the blooded animals. body. It acts directly on the nervous Horses, mules, and asses, which are system. It is so potent that a mere highly susceptible, may contract the prick with a hypodermic needle con- disease from any type of wound but taminated with it may be enough to most frequently from wounds of the cause symptoms of tetanus in people. feet. C. tetani, like the germs that cause In , which are rather suscepti- blackleg and malignant edema, thrive ble, the infection sometimes occurs in the absence of air. They become after castration, docking, and shear- especially active and dangerous when ing; in the umbilical (navel) cord of they are implanted in injured tissue lambs during birth; or in ewes during 238 Yearbook of Agriculture 1956 parturition. Cows may get infection the individuals, the species of animal, following parturition and calves after and severity of the infection. Animals castration. that recover often arc sick a month. Cases are observed occasionally in Tetanus is not hard to diagnose be- swine, dogs, and cats. cause its symptoms are unusual. Rigid- Poultry is highly resistant. ity of the muscles is one of the most constant and typical symptoms. No SYMPTOMS appear in most cases in i typical lesions are found on post- to 2 weeks after the germs enter the mortem examination, but microscopic body. Sometimes—depending on the examination of stained smears made type of primary injury, the character from deep portions of wounds may of the healing process, and the degree reveal the typical drumstick-shaped of infection—the symptoms may not organisms of tetanus. appear for several weeks. Very young animals may develop symptoms in less PREVENTION of tetanus depends first than a week. on cleanliness. Cleanliness in all oper- The first signs of the disease usually ations includes strict aseptic surgical are manifested about the head. Chew- procedures and the use of sterile surgi- ing is difficult at first, and swallowing cal instruments. is slow and awkward. Spasms spread Animals should be housed during rapidly from one group of muscles to parturition and following surgery in another and make them rigid. Eating clean, dust-free quarters. may become impossible when the mus- Prompt and proper attention should cles used in chewing are affected and be given to deep wounds—the removal the jaws are ''locked." of dirt and other foreign material, The nictitating mcmibrane (the in- proper drainage with surgery, and ir- ner, or third, eyelid between the lower rigation of the wound with suitable eyelid and the eyeball proper) pro- medicaments, such as hydrogen per- trudes up on the surface of the eyeball. oxide. This is noticeable especially in the Stables, corrals, paddocks, or pas- horse. tures used by horses and other live- The legs are spread and stiffened, stock should be kept free of sharp giving a straddling gait and the ap- objects which are apt to cause injuries. pearance of a sawhorse. The tail is In known tetanus districts, routine elevated and stiff. The ears are held preventive of animals rigidly erect. Constipation commonly against tetanus and immediate treat- occurs. The breathing is rapid and ment of injured animals with tetanus forced. The heart action may or may antitoxin following wounds will ma- not be quickened. Usually there is little terially reduce the chances of infection. or no except in the severe cases and then just before . THE PREVENTIVE immunizing agents The muscles may tend to relax at against tetanus are of two types, tet- intervals, but they contract instantly, anus antitoxin and tetanus . like a spring, at the slightest noise, Tetanus antitoxin is produced from a ray of light, or a touch. Death is the blood serum of horses. It is stand- usually due to exhaustion or nonfunc- ardized as to potency, so that a given tion of the vital organs. Pneumonia, amount neutralizes a specific amount which results from the inhalation of of toxin. Injected into susceptible ani- water, saliva, feed, or improperly ad- mals, it confers a passive or temporary ministered medicines, is a frequent against the disease. As a complication. preventive, it should be injected im- Death usually comes 7 or lo days mediately following an injury and after the first symptoms appear. Mor- not after symptoms occur. tality is 55 to 90 percent, depending on The tetanus toxoid is prepared by 239 treating the toxin with formalin to be located, to provide adequate drain- inactivate its toxicity. The refined age and to keep it open by irrigation formalized toxoid, which has largely with a suitable antiseptic. replaced antitoxin for immunization, Confinement of affected animals in especially in man, confers an active clean, cool, quiet, darkened quarters immunity against the toxin in about is advantageous. 2 weeks after its injection. The im- If tetanus antitoxin is indicated, it munity lasts about a year and can be should be given in large, repeated increased by booster injections. The doses. Sedatives of various types are use of tetanus toxoid in animals and commonly employed to produce relax- man has become a routine practice in ation of the muscles. Artificial feeding some areas where tetanus is prevalent. may be required. The prevalence of tetanus in ani- Veterinarians have reported that the mals and man has decreased because administration of , alone or of improved methods of wound treat- as an adjunct to antitoxin, has given ment, better hygiene, and preventive good results in the treatment of some with tetanus toxoid. The cases that show early symptoms of incidence of tetanus in troops during tetanus. the First World War was greatly re- When attempts are made to treat a duced by better treatment of battle case of tetanus, the procedure should wounds and administration of tetanus be carried out under the supervision antitoxin. Its incidence in the Second of a veterinarian. World War was negligible, because immunization of all the troops with CD. STEIN, a graduate of the Univer- tetanus toxoid was a routine measure. sity of Pennsylvania, is a veterinarian in the Animal Disease and Parasite Research TREATMENT of an established case of Branch of the Agricultural Research Service. tetanus in an animal that shows well- He has been with the Department of Agricul- marked symptoms has little value. ture since igii, during which time his re- Chances for recovery are improved if search has contributed fundamental irforma- treatment is started early. It is first tion for a better understanding of anthrax, essential to open the wound through equine infectious anemia, and other infec- which the infection entered, if it can tious diseases of livestock.

Listeriosis

H. E. BIESTER AND L. H. SCHWARTE

LISTERIOSIS, an infectious disease, names have been used for the organ- is caused by a bacterial organism that ism—Bacterium monocytogenes, Listerella afi'ects animals and people. hepatolytica, L. monocytogenes, Coryne- Three British scientists first recov- bacterium parvulum, and mono- ered the organism from laboratory cytogenes. It has been designated as rabbits and guinea pigs in 1926. They monocytogenes since 1948. The named it Bacterium monocytogenes. Later disease formerly was known as lister- a similar organism was isolated from ellosis. some rodents in South Africa. Various Various investigators have found