Bacillus anthracis

“ There is a certain malady known, when it attacks cattle and sheep, as ‘charbon’ or ‘sang de rate,’ and when it attacks man, as ‘woolsorter’s disease.’ The term ‘anthrax’ covers the disease in both beast and{121} man; and anthrax is produced by a bacterium known as Bacillus anthracis, which had been recognized and was accused of causing the disease before Pasteur began to interest himself in such matters. It annually carried off 20 per cent. ”

“ The post-mortem appearances in internal anthrax are such as are usually observed in septicaemia, but in addition evidence of extensive inflammation of the lungs, pleura and bronchial glands has in most cases been met with. The blood and other fluids and the diseased tissues are found loaded with the Bacillus anthracis. ”

“ If those members of the herd, that show no hyperthermia or other symptom of anthrax, can be held apart as a separate herd, in a disinfected place and under careful thermometric observation, their dairy products may be used.
Immunization. A number of different methods have been practiced of rendering animals refractory to the bacillus anthracis, but all are apparently based on the production in the system of defensive products, as the result of a nonlethal poisoning with anthrax toxins. It is true of anthrax as of many other infections that a first attack protects against a second. ”

“ DEFINITION.—Anthrax is an acute, infectious, bacteridian disease, occurring mostly in the Herbivora and Omnivora, but communicable to other mammals (including man) , to birds, and even fishes. Its local manifestations are exceedingly varied in kind, but the malady is characterized by the presence in the tissues or blood, or both, of specific spherical and linear bacteria (micrococcus and bacillus anthracis) , leading to arrest of hæmatosis, to disintegration of the blood-globules, to sanguineous engorgement of the spleen, to capillary embolism, and to a spreading gangrenous inflammation. ”

“ In the cultures prepared with the view of attenuating the microbe, it is the action of the oxygen of the air which renders the bacteridium less virulent. It should be subjected to a temperature of from 42° to 43° in the case of Bacillus anthracis, to enable it to multiply, and at the same time to check the production of spores which might make the liquid too powerful. At the end of the week, the culture, which at first killed the whole of ten sheep, killed only four or five out of ten. ”

“ In some cases when organisms not the natural inhabitants of water are introduced into it, a large proportion of them are at first destroyed, but a multiplication in numbers takes place afterward. The Bacillus anthracis in its bacillus form is destroyed with comparative ease, but the spores have remarkable vitality. ”

“ Afterward, Koch succeeded in making cultures of them, and reproduced the disease by inoculating animals with these cultures; yet it was said, so late as 1876, that the bacillus anthracis was not the cause of anthrax, but only the sign of it: "Along with the bacilli, there are blood-cells and blood-plasma, and these contain the true amorphous virus of anthrax." Then came Pasteur's work, and reached its end in the experiments at Chartres, and the famous test-inoculations (1881) at Pouilly-le-Fort. ”

“ It may be cultivated in chicken-broth, neutralized by potash, while it soon dies in the extract of yeast, which is so well adapted to Bacillus anthracis. The microbe of this disease may also be attenuated by culture, and it may be done more easily than in the case of anthrax, since it is not necessary to raise the temperature, as the bacterium of fowl-cholera does not produce spores under culture. Pasteur has therefore been able to prepare an attenuated virus well adapted to protect fowls from further attacks of this disease. ”

“ The _bacillus anthracis_ (Fig. 27) , the largest of the known pathogenic bacteria, occurs in groups or in chains made up of numerous bacilli, each bacillus measuring from 6 to 8 [micron] in length. The organisms are found in enormous numbers throughout the bodies of animals that have died of anthrax, and are readily recognised and cultivated. Sporulation only takes place outside the body, probably because free oxygen is necessary to the process. In the spore-free condition, the organisms are readily destroyed by ordinary germicides, and by the gastric juice. ”

“ The existence of micro-organisms in countless numbers is no new fact, but the influence they may exert over living tissues has only lately become the subject of earnest attention. So long as they were not known to have any practical bearing upon human welfare, they interested almost nobody, but when, however, it was shown that putrefaction of meat is due to the agency of the bacterium termo, and the decomposition of albumen to the bacillus subtilis; when anthrax in cattle and sheep was found to depend on the bacillus anthracis, and that in human beings it caused malignant pustules ”

“ If the malady affects domestic animals generally, is especially virulent in cattle, sheep and horses, and attacks even man; if the district is subject to anthrax, or of a rich damp soil which would be favorable to the preservation of bacillus anthracis; if it is in the line of watershed from stock markets, abattoirs, tanneries, rendering works, glue factories, packing houses, sausage factories, or phosphate works ”

“ In animals, anthrax is also called charbon, splenic fever, or splenic apoplexy: in man, the name of malignant pustule is given to the sore at the point of accidental inoculation, and the name of woolsorter's disease is given to those cases of anthrax where the lungs are infected by inhalation of the spores of the bacillus anthracis. ”

“ Paul Bert showed that oxygen under high pressure (twenty atmospheres) kills the Bacillus anthracis. Toussaint, Chamberland, and Roux (1880-'86) added dilute carbolic, chromic, and sulphuric acids to nutrient media for the same purpose. Klein (1888) used also very small quantities of corrosive sublimate for the same purpose. Arloing (1886) showed that bright sunlight has also an attenuating effect on cultivations in fluid media. ”

“ It was repeatedly found that the matter taken from the vesicle during the progress of the disease, as well as the blood in the body after death, contained the Bacillus anthracis, and when inoculated into small animals produced rapid death, with all the symptoms and post-mortem appearances characteristic of che disease as known to affect them. ”

“ Some new light has been thrown upon the subject of pathogenic organisms in air by Neisser in his investigations concerning the amount and rate of air-currents necessary to convey certain species through the atmosphere. He states that the bacteria causing diphtheria, typhoid fever, plague, cholera, and pneumonia, and possibly the common Streptococcus pyogenes, are incapable of being carried by the molecules of atmospheric dust which the ordinary insensible currents of air can support, whilst Bacillus anthracis, B. pyocyaneus, and the bacillus of tubercle are capable of being aërially conveyed. ”

“ Scotland, and Ireland, and in large quantities in the United States (Pennsylvania) , and near Swansea (South Wales) . See Coal.
An ́thrax, a fatal disease to which animals are subject, always associated with the presence of an extremely minute micro-organism (Bacillus anthrăcis) in the blood. It attacks cattle more frequently than other animals; sheep, horses, pigs, dogs, and fowls are liable to anthrax, but not cats. The mode of infection in animals is chiefly by ingestion. ”

“ In places they are so densely packed as to form obstructions to the onward flow of blood. In cultures they are in chains end to end, having as a rule equal interbacillary spaces. In cultures long filaments and threads occur. The exact shape of the bacillus depends, however, upon two things: the staining and spore formation. Both these factors may very materially modify the normal shape. The spores of anthrax are oval endospores, produced only in the presence of free oxygen, and at any temperature between 18 and 41° C. On account of requiring free oxygen, they are formed only outside the body. ”

“ The bacillus of anthrax, under certain conditions, retains its vitality for a long time, and rapidly grows when it finds a suitable field in which to develop, its mode of multiplication being by scission and the formation of spores, and depending, to a great extent at least, on the presence of oxygen. The morbid action of the bacillus is indeed said to be due to its affinity for oxygen; by depriving the red corpuscles of the blood of that most essential gas, it renders the vital fluid unfit to sustain life. ”

“ ETIOLOGY.—That anthrax in man is almost invariably derived from the lower animals by infection is now undoubted, while for the direct infection of man, as of animals, by the germs propagated in the soil, there is no absolute proof. The latter mode of propagation has only been recognized in the Herbivora, which are so much more exposed to contamination from the soil; yet, abstractly, there is no reason to suppose that man is less susceptible to the earth-grown bacillus than to that produced in the animal, if only he were as frequently exposed to its infection. ”

“ Investigations into fermentation and putrefaction followed each other rapidly, and in 1863 Davaine claimed that Pollender's bacillus of anthrax, which was found in the blood and body tissues of animals dead of anthrax, was the cause of that disease. From that time to this in every department of biology bacteria have been increasingly found to play an important part. They cause changes in milk, and flavour butter; they decompose animal matter, yet build up the broken-down elements into compounds suitable for use in nature's economy; they assist in the fixation of free nitrogen ”

“ The great tenacity of life in the spores in heat and cold, dryness and wet, excluded from air and under several atmospheres of oxygen, in the midst of putrefaction and in pure watery fluids, well accounts for the persistence of infection in buildings and localities where the poison has gained a foothold. In order to their destruction in a natural manner it seems necessary that they should germinate and develop into the anthrax micrococcus, bacillus, or mycelium. ”

“ Contagion may take place both by introduction into wounds, and from the mucous membrane of the intestines or lungs, both by vegetative cells and by spores; in intestinal anthrax, however, only by spores. The Bacillus multiplies as soon as it has entered the blood, and the anthrax disease commences. The Bacilli not only give off poison, [40] but also deprive the blood of its oxygen. Vegetative cells only occur in living animals. This species is a facultative parasite which in the first stage is a saprophyte, and only in this condition forms spores. ”

“ Whether bacteria will be destroyed or not after they have been ingested by the leucocytes will depend upon the digestive powers of the latter, and these probably vary in different species of animals. The blood serum has a direct bactericidal action on certain bacteria, as tested outside the body, and this also varies in different animals. Observations made on this property with respect to the anthrax bacillus at first gave the hope that it might explain variations in natural immunity. Thus the serum of the white rat, which is immune to anthrax, kills the bacillus ”

“ The grave character of internal anthrax, however, is such that resort may be had to one of the various antitoxins, antidotal cultures, serums, and immunizing agents that have proved useful in different hands. Unfortunately such agents do not seem to act in the same manner on all genera, and what has been effective in one of the lower animals may fail in the human being. Thus Roger found that sterilized cultures of bacillus prodigiosus retarded or obviated anthrax in rabbits, but hastened its progress in the Guinea pig. ”

“ They exist in our food and drink; but the intestine is, one may say, a natural home in which many exist without harm to the body. For surgical purposes their existence is most important, first, in the earth, where, as I have already shown, the bacillus of lockjaw is most frequently found. So, too, the bacillus of wool-sorters’ disease (Anthrax) exists in the earth. If an animal dying of anthrax is buried, worms coming from the carcass up through the ground carry the infection, so that other animals grazing over this surface will become readily infected. ”

“ Fresh Air, like sunlight, should be employed as a valuable auxiliary, not as an agent to be depended upon apart from systematic disinfection. The experiments of Downes and Blunt showed that light and oxygen together accomplished what neither alone could do. The presence of air in anthrax increases danger. The anthrax bacillus does not form spores in an animal suffering from this disease, and does not do so post mortem, unless the animal is dissected. ”

“ Pasteur says that he has found by experiment that when attenuated varieties of the anthrax bacillus form spores, these again reproduce the same pathogenic variety, so that cultures of each degree of attenuation can be maintained indefinitely. ”

“ Certain bacteria are disease-producing or pathogenic. The largest of these is the Bacillus of Anthrax, a disease common in sheep and oxen, and sometimes communicated to man. This bacillus is 1·2 μ thick and 6 to 8 μ long. When an animal dies of this disease it should be buried without cutting the skin. When exposed to the air this bacillus forms minute spores, very difficult to destroy. They may live for several years in pits in which animals dying from anthrax have been buried. Butchers have died when inoculated through cracked fingers when dressing the carcase of a cow which has had anthrax. ”