Symptoms.—The clinical diagnosis is not always easy. The most frequent primary lesion is in the face. The first symptom is a sense of itching, followed by a red spot resembling a flea-bite; a small vesicle forms soon afterward, con taining a bluish fluid. The surroundingskin is somewhat indurated and swelled. This changes into a black spot, which' soon becomes gangrenous. If the edema continues fresh crops of vesicles often appear, undergoing the same change, and infecting the adjacent lymphatic glands. The period of incubation is from one to• three days, while the development of the local symptoms occupies from three to nine days. A line of demarkation may then form, and the slough separates. No pus is present. General disturbance be gins only a day or two after the mani festation of the disease. There may be no fever, but in some cases, especially when the face is involved, a sudden rise of temperature may present itself, de noting a dangerous condition.
Headache, nausea, and pain in the muscles appear, with a weak and rapid heart. There is slight icterus. The prostration is great, and the last stages of the disease finds the patient almost in the algid stage of cholera.
Case in which high fever (104.S° F.), with delirium, feeble pulse, and sweating, developed on the fourth day, previous to which the case had presented the char teristics of ordinary phlegmonous cellu litis. Recovery after excision, cauteriza tion, and inoculation with cultures of bacillus pyocyaneus. C. E. Hammack (N. Y. Med. Jour., July 17, '97).
When infection takes place through the alimentary canal, the disease begins with debility, depression of spirits, ma laise, and probably a chill. In addition. the symptoms point to the intestines. Haemorrhages occur from the mouth and nose; vomiting is followed by a bloody diarrhoea. The diagnosis is, however, extremely difficult, and the microscopical examination of the blood or an inocula tion of an animal furnishes the only con clusive evidence.
Difference between effects of the local ization of the pneumococcus and that of the anthrax bacillus. In the former true encephalitic phenomena are produced; in the latter, only hemorrhages. This is evidently ascribable to a difference in the metabolic products of the respective micro-organisms. E. Fraenkel (Zeit. f. Hyg. u. Infectionsk., B. 27, II. 3, '93).
Etiology. — Anthrax was one of the first diseases traced to a specific micro organism.
Pollender discovered in 1349 small rod-shaped bodies in the blood of ani mals suffering from anthrax, but Da value, in 1863, proved their etiological significance. Pasteur and Koch, observ ing that the bacilli bore spores, culti vated them successfully outside of the body, and then produced the disease by inoculating animals with the pure cult The anthrax bacilli are large rods, with a rectangular form, caused by the very slight rounding of the corners.
They measure 5 to 20 microns in length and are 1 to 1.25 microns in breadth. They form long threads, in which the single bacterium can be made out. At times isolated rods occur. In this stage granular bodies appear in the protoplasm of the bacilli. They eventually form glistening oval spores, one of which lies in each segment of the long thread, giv ing the threads an appearance of a string of beads. The bacilli soon break up, and the spores become free. In this condi tion the spores become highly resisting and can be preserved a very long time. If again placed under favorable circum stances each spore will germinate into a mature cell. Spore-formation takes place only at temperatures ranging from 13° to 43° C., 37.5° C. being the most favor able temperature.
The anthrax bacilli can rapidly be stained by aqueous solutions of aniline dyes, and also by Gram's method. The spores are best stained at a high tern perature by means of Ehrlich's aniline water-fuchsin solution or Ziehl's solu tion containing carbolic acid, instead of Ehrlich's fuchsia solution.
The virulence of anthrax bacilli can be attenuated in. various ways, such as subjecting them to a high or low tem perature or making the culture grow for a long time—twenty-four days or so— at a temperature of 42° or 43° C. By treating them in some such manner it is possible to render anthrax bacilli en tirely innocuous (Koch, Loeffler). Pas teur rendered sheep and cattle immune against anthrax by inoculating them with a culture which grew at a tempera ture of 42° C.
Dogs, pigs, and the majority of birds are immune from anthrax; also rats and frogs under ordinary conditions. But if a frog in whose lymph-sac are placed anthrax bacilli is put in an incubating apparatus, he will quickly die of anthrax. Birch-Hirschfeld and others have proved that anthrax bacilli can be transmitted from mother to fcetus in utero.
Experiments to determine the influ ence of the serum of immunized animals. A sheep was immunized until it could bear the injection of 7 agar-agar cult ures with but slight elevation of tem perature. A lamb was immunized like wise to the highest degree and blood was taken from the carotid artery of both animals in order to obtain serum. With the serum of the sheep it was actu ally possible to save from death a rabbit in which an extremely virulent culture of anthrax was injected, either after or simultaneously with the serum. Evi dent therapeutic results were obtained with this serum in animals that had received the anthrax bacilli previous to the injection of serum.