A text-book upon the pathogenic bacteria, for students of medicine and physicians

Front matter

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Preface To The Fourth Edition

The extremely gratifying reception accorded to the previous editions of this work has stimulated both author and publisher to endeavor in every way to make it merit continued approbation. It has therefore been practically rewritten, the force and accuracy of diction being improved, old matter eliminated, much new matter inserted, and the subjects treated brought up to date. The chapters upon Infection and Immunity have been greatly extended to permit the introduction of the many new facts recently added to our knowledge of the subject. By using a smaller type it has been possible to increase the amount of material without adding to the number of pages.

The value of the work as a book of reference has been greatly enhanced by the introduction of a large number of references to the literature of bacteriology. These have been thoughtfully chosen, and will in nearly all cases give the sources of the original descriptions of the micro-organisms treated, the important methods described, and the newest additions to knowledge of the subject. In a few cases references have been made to papers whose interest to the student depends upon some unusually suggestive thought, some exceptionally ingenious method, or some remarkably thorough piece of work. An index of authors has also been introduced, to aid students engaged in literary work.

Although the chapters devoted to General Facts about Bacteria and the Technic of Bacteriology have been much improved, and should enable the student to thoroughly comprehend and perform the necessary manipulations, The Pathogenic Bacteria must not be mistaken for a general treatise upon bacteriology or for a laboratory guide. It treats of the pathogenic bacteria, and contains only as much general information pertaining to the subject as will permit an intelligent understanding of their place in nature, their biology, morphology, and relation to disease. It is thus essentially a work for the use of physicians, students of medicine, and sanitarians.

Joseph McFarland.

Preface

The following pages are intended to convey to the reader a concise account of the technical procedures necessary in the study of bacteriology, a brief description of the life-history of the important pathogenic bacteria, and sufficient description of the pathological lesions accompanying the micro-organismal invasions to give an idea of the origin of symptoms and the causes of death.

The work being upon Pathogenic Bacteria, it does not cover the whole scope of parasitology, and the parasites of higher orders are all omitted. Malaria and amebic dysentery are omitted as logically as tape-worms and pediculi. The higher fungi are also omitted, both because they are not bacteria and because their proper consideration would make a small book in itself

In leaving out the non-pathogenic bacteria of course a stumbling-block was encountered. The Sarcina ventriculi, for instance, may be a cause of dyspepsia, yet can scarcely be regarded as pathogenic, and, together with other similar bacteria of questionable deleterious operation, has been omitted ; on the other hand, it has been thought advisable to include and describe somewhat at length a long list of spirilla similar to, and probably closely allied with, the spirillum of cholera, yet not the cause of any particular diseased condition.

lO PREFACE.

The aim has been to describe only such bacteria as can be proven pathogenic by the lesions or toxins which they engender, and, while considering them, to mention as fully as is necessary the species with which they may be confounded.

The book, of course, will find its proper sphere of usefulness in the hands of medical students ; its pages, however, will be found to contain much that will be of interest and profit to those practitioners of medicine who graduated before modem science had thrown its light upon the etiology of disease.

In writing this work the popular text-books have been drawn upon. Hiippe, Fliigge, Sternberg, Frankel, Giinther, Thoinot and Masselin, and others have been freely consulted.

The illustrations are mainly reproductions of the best the world affords, and, being taken from the great standards, are surely superior to anything new covering the same ground. Credit has carefully been given for each

illustration.

J. McF.

Philadelphia, Feb. i, 1896.

Part I. General Considerations

Biology, chemistry, medicine, and surgery, in their evolution, contributed to a new branch of knowledge whose subsequent development has been of inestimable importance to each. Indeed, bacteriology illustrates the old adage, *'The child is father of the man," for while it is in part the offspring of the medicine of the past, it has established itself as the dictator of the medicine of the present and future, especially so far as concerns the infectious diseases.

THE EVOLUTION OF BACTERIOLOGY.

I. BIOLOGIC CONTRIBUTIONS! THE DOCTRINE OF SPONTANEOUS GENERATION.

Among the early Greeks we find that Anaximander (43d Olympiad, 610 B. C.) of Miletus held the theory that animals were formed from moisture. Empedocles of Agrigentum (450 B. C.) attributed to spontaneous generation all the living beings which he found peopling the earth. Aristotle (384 B. C.) is not so general in his view of the subject, but asserts that '* sometimes animals are formed in putrefying soil, sometimes in plants, and sometimes in the fluids of other animals/*

Three centinies later, in his disquisition upon the Pythagorean philosophy, we find Ovid defending the same doctrine of spontaneous generation, while in the Georgics Virgil gives directions for the production of bees.

The doctrine of spontaneous generation of life was not only current among the ancients, but we find it persisting through the Middle Ages, and descending to our own generation. In 1542, in his treatise called ** De Subtilitate,*' we 2 17 find Cardan asserting that water engenders fishes, and that many animals spring from fermentation. Van Helmont gives special instructions for the artificial production of mice, and Kircher in his '* Mundus Subterraneus " (chapter *'De Panspermia Rerum") describes and actually figures certain animals which were produced under his own eyes by the transforming influence of water on fragments of stems from different plants.*

About 1686, Francesco Redi seems to have been the first to doubt that the maggots familiar in putrid meat arose de novo: ** Watching meat in its passage from freshness to decay, prior to the appearance of maggots, he invariably observed flies buzzing around the meat and frequently alighting on it. The maggots, he thought, might be the halfdeveloped progeny of these flies. Placing fresh meat in a jar covered with paper, he found that although the meat putrefied in the ordinary way, it never bred maggots, while meat in open jars soon swarmed with these organisms. For the paper he substituted fine wire gauze, through which the odor of the meat could rise. Over it the flies buzzed, and on it they laid their eggs, but the meshes being too small to permit the eggs to fall through, no maggots generated in the meat; they were, on the contrary, hatched on the gauze. By a series of such experiments Redi destroyed the belief in the spontaneous generation of maggots in meat, and with it many related beliefs.*'

In 1683 Anthony van Leeuwenhoek, justly called the ** Father of microscopy,*' demonstrated the continuity of arteries and veins through intervening capillaries, thus affording ocular proof of Harvey's discovery of the circulation of the blood; discovered bacteria, seeing them first in saliva, discovered the rotifers, and first saw the little globules in yeast which Latour and Schwann subsequently proved to be plants.

Leeuwenhoek involuntarily reopened the old controversy about spontaneous generation by bringing forward a new world, peopled by creatures of such extreme minuteness as to suggest not only a close relationship to the ultimate molecules of matter, but an easy transition from them.

In succeeding years the development of the compound microscope showed that putrescent infusions, both animal and vegetable, teemed with minute living organisms. * See Tyndall: " Floating Matter in the Air."

AbW Lazzaro Spallanzani (1777) filled flasks with organic infusions, sealed their necks, and, after subjecting their contents to the temperature of boiling water, placed them under conditions favorable for the development of life, without, however, being able to produce it. SpaUanzani's critics, however, objected to his experiment on the groimd that air is essential to life, and that in his flasks the air was excluded by the hermetically sealed necks.

Schulze (1836) set the objection aside by filling a flask only half full of distilled water, to which animal and vegetable matters were added, boiling the contents to destroy the vitality of any organisms which might already exist in them, then sucking daily into the flask a certain amount of air which was passed through a series of bulbs containing •concentrated sulphuric acid, in which it was supposed that whatever germs of life the air might contain would be destroyed. This flask was kept from May to August; air was passed through it daily, yet without the development of any infusorial life.

It must have been a remarkably germ-free atmosphere in which Schulze worked, for, as was shown by those who repeated his experiment, under the conditions that he regarded as certainly excluding all life, germs can readily enter with the air.

The term ** infusorial life*' having been used, it is well to remark that during all the early part of their recognized existence the bacteria were regarded as animal organisms and classed among the infusoria.

Tyndall, stimulated by the work of Pasteur, conclusively proved that the micro-organismal germs were in the dust suspended in the atmosphere, and not ubiquitous in their distribution. His experiments were very ingenious and are of much interest. First preparing light wooden chambers, with a large glass window in the front and a smaller window in each side, he arranged a series of test-tubes in the bottom, half in and half out of the chamber, and a pipet, working through a rubber diaphragm, in the top, so that when desired the tubes, one by one, could be filled through it. Such chambers were allowed to stand until all the contained dust had settled, and then submitted to an optical test to determine the purity of the contained atmosphere by passing a powerful ray of light through the side windows. When viewed through the front, this ray was visible only so long as there were particles suspended in the atmosphere to reflect it. When the dust had completely settled and the light ray had become invisible because of the purity of the contained atmosphere, the tubes were cautiously filled with urine, beef-broth, and a variety of animal and vegetable broths, great care being taken that in the manipulation the pipet should not disttu-b the dust. Their contents were then boiled by submergence in a pan of hot brine placed beneath the chamber, in contact with the projecting ends of the tubes, and subsequently allowed to remain undisturbed for days, weeks, or months. In nearly eVery case life failed to develop in the infusions after the purity of the atmosphere was established.

The following extracts from Tyndall's work * will illustrate how slowly the doctrine of spontaneous generation* was abandoned:

"At a meeting of the Pathological Society of London, held April 6, 1875, the 'germ theor>'' of disease was formally introduced as a subject for discussion, the debate being continued with great ability and earnestness at subsequent meetings. The conference was attended by many distinguished medical men, some of whom were profoundly influenced by the arguments, and none of whom disputed the facts brought forward against the theory on that occasion.

**The leader of the debate, and the most prominent speaker, was Dr. Bastian, to whom also fell the task of replying on all the questions raised.

'*The coexistence of bacteria and contagious disease was admitted; but, instead of considering these organisms as probably the essence, or an inseparable part of the essence, of the contagium, Dr. Bastian contended that they were pathological products spontaneously generated in the body after it had been rendered diseased by the real contagium.

**The grouping of the ultimate particles of matter to form living organisms Dr. Bastian considered to be an operation as little requiring the action of antecedent life as their grouping to form any of the less complex chemical compounds." "Such a position must, of course, stand or fall by the evidence which its supporter is able to produce, and accordingly Dr. Bastian appeals to the law and testimony of experiment as demonstrating the soundness

* Op. cit.

of his view." **He seems quite aware of the gravity of the matter at hand ; this is his deliberate and almost solemn appeal: *With the view of settling these questions, therefore, we may carefully prepare an infusion from some animal tissue, be it muscle, kidney, or liver; we may place it in a flask whose neck is drawn out and narrowed in the blowpipe flame; we may boil the fluid, seal the vessel during ebullition, and, keeping it in a warm place, may await the result, as I have often done. . . . After a variable time the previously heated fluid within the hermetically sealed flasks swarms more or less plentifully with bacteria and allied organisms, even though the fluids have been much degraded in quality by exposure to the temperature of 212-° F., and have in all probability been rendered far less prone to engender independent living units than the unheated fluids in the tissues would be.' "

n. CHEMIC CONTRIBUTIONS I FERMENTATION AND PUTREFACTION*

As in the world of biology the generation of life was an all-absorbing problem, so in the world of chemistry the phenomena of fermentation and putrefaction were inexplicable so long as the nature of the ferments was not understood.

In the year 1837 Latour and Schwann succeeded in demonstrating that the minute oval bodies which had been observed in yeast since the time of Leeuwenhoek were living organisms — vegetable forms^-capable of growth.

So long as yeast was looked upon as an inert substance it was impossible to understand how it could impart fermentation to other substances; but when it was shown by Latour that the essential element of yeast was a growing plant, the phenomenon became a perfectly natural consequence of life. Not only the alcoholic, but also the acetic, lactic, and butyric fermentations have been shown to result from the energy of low forms of vegetable life, chiefly bacterial in nature. Prejudice, however, prevented many chemists from accepting this view of the subject, and Liebig strenuously adhered to his theory that fermentation was the result of the internal molecular movements which a body in the course of decomposition communicates to other matter whose elements are connected by a very feeble aflSnity.

Pasteur was the first to prove that fermentation is an ordinary chemic transformation of certain substances, taking place as the result of the action of living cells, and that the capacity to produce it resides in all animal and vegetable cells, though in varying degree.

In 1862 he published a paper **0n the Organized Corpuscles Existing in the Atmosphere," in which he showed that many of the floating particles collected from the atmosphere of his laboratory were organized bodies. If these were planted in sterile infusions, abimdant crops of micro-organisms were obtained. By the use of more refined methods he repeated the experiments of others, and showed clearly that '*the cause which communicated life to his infusions came from the air, but was not evenly distributed through it."

Three years later he showed that the organized corpuscles which he had found in the air were the spores or seeds of minute plants, and that many of them possessed the property of withstanding the temperature of boiling water — a property which explained the peculiar results of many previous experimenters, who failed to prevent the development of life in boiled liquids inclosed in hermetically sealed flasks.

Chevreul and Pasteur, by having proved that animal solids do not putrefy or decompose if kept free from the access of germs, suggested to surgeons that putrefaction in wounds is due rather to the entrance of something from without than to changes within. The deadly nattue of the discharges from putrescent wounds had been shown in a rough manner by Gaspard as early as 1822 by injecting some of the material into the veins of animals.

ra. MEDICAL AND SURGICAL CONTRIBUTIONS j THE STUDY OF THE INFECTIOUS DISEASES.

Probably the first writing in which a direct relationship between micro-organisms and disease is suggested is by Varro, who says: "It is also to be noticed, if there be any marshy places, that certain minute animals breed [tjiere] which are invisible to the eye, and yet, getting into the system through mouth and nostrils, cause serious disorders (diseases which are difficult to treat)."

Surgical methods of treatment depending for their success upon exclusion of the air, and of course, incidentally if unknowingly, exclusion of bacteria, seem to have been practised quite early. Theodoric, of Bologne, about 1260 taught that the action of the air upon wounds induced a pathologic condition predisposing to suppuration. He also treated wounds with hot wine fomentations. The wine was feebly antiseptic, kept the surface free from bacteria, and the treatment was, in consequence, a modification of what in later centmies formed antiseptic surgery.

Henri de Mondeville in 1306 went even further than Theodoric, whom he followed, and taught the necessity of bringing the edges of a wound together, covered it with an exclusive plaster compoimded of turpentine, resin, and wax, and then applied the hot wine fomentation.

In 1 67 1 Kircher wrote a book in which he expressed the opinion that puerperal fever, piupura, measles, and various other fevers were the result of a putrefaction caused by worms or animalcules. His opinions were thought by his contemporaries to be founded upon too little evidence, and were not received.

Plencig, of Vienna, became convinced that there was an undoubted connection between the microscopic animalcules exhibited by the microscope and the origin of disease, and advanced this opinion as early as 1762. Unfortunately, the opinions of Plencig seem not to have been accepted by others, and were soon forgotten.

In 1704 John Colbach described **a new and secret method of treating wounds by which healing took place quickly, without inflammation or suppuration."

Boehm succeeded in 1838 in demonstrating the occurrence of yeast plants in the stools of cholera, and conjectiu^ that the process of fermentation was concerned in the causation of that disease.

In 1840 Henle, considering all the evidence that had been collected, determined that the cause of the infectious diseases was to be sought for in minute living organisms or fungi. He may be looked upon as the real propounder of the Germ Theory op Disease, for he not only collected facts and expressed opinions, but also investigated the subject ably. The requirements which he formulated in order that the theory might be proved were so severe that he was never able to attain to them with the crude methods at his disposal. They were so ably elaborated, however, that in after years they were again postulated by Koch, and it is only by strict conformity with them that the definite relationship between bacteria and disease has been determined.

Briefly summarized, these requirements are as follows:

1. A specific microHDrganism must be constantly associated with the disease.

2. It must be isolated and studied apart from the disease.

3. When introduced into healthy animals it must produce the disease.

In 1849 J. K. Mitchell, in a brief work upon the **Cryptogamous Origin of Malarious and Epidemic Fevers/' foreshadowed the germ theory of disease by collecting a large amount of evidence to show that malarial fevers were due to infection by fungi.

PoUender (1849) and Davaine (1850) succeeded in demonstrating the presence of the anthrax bacillus in the blood of animals suffering from and dead of that disease. Several years later (1863) Davaine, having made numerous inoctdation experiments, demonstrated that this bacillus was the maieries morhi of the disease. The bacillus of anthrax was probably the first bacterium shown to be specific for a disease. Being a very large bacillus and a strongly vegetative organism, its growth was easily observed, while the disease was one readily communicated to animals.

In 1873 Obermeier observed that actively motile, flexible spiral organisms were present in large numbers in the blood of patients in the febrile stages of relapsing fever.

K^ebs, who was one of the pioneers of the germ theory, published, in 1872, a work upon septicemia and pyemia, in which he expressed himself convinced that the causes of these diseases must come from without the body. Billroth, however, strongly opposed such an idea, asserting that fungi had no especial importance either in the processes of disease or in those of decomposition, but that, existing everywhere in the air, they rapidly developed in the body as soon as through putrefaction a **Faulnisszymoid,*' or through inflammation a **Phlogistischezymoid,*' supplying the necessary feeding-grounds, was produced.

In 1875 the number of scientific men who had entirely abandoned the doctrine of spontaneous generation and embraced the germ theory of disease was small, and most of those who accepted it were experimenters. A great majority of medical men either believed, like Billroth, that the presence of fungi where decomposition was in progress was an accidental result of their universal distribution, or, being still more conservative, adhered to the old notion that the bacteria, whose presence in putrescent wounds as well as in artificially prepared media was unquestionable, were spontaneously generated there.

Before many of the important bacteria had been discovered, and while ideas upon the relation of micro-organisms to disease were most crude, some practical measures were suggested that produced greater agitation and incited more observation and experimentation than anything suggested in surgery since the introduction of anesthetics — namely, antisepsis,

**It is to one of old Scotia's sons, Sir Joseph Lister, that the everlasting gratitude of the world is due for the knowledge we possess in regard to the relation existing between micro-organisms and inflammation and suppuration, and the power to render wounds aseptic through the action of germicidal substances." *

Lister, convinced that inflammation and suppuration were due to the entrance of germs from the air, instruments, fingers, etc., into woimds, suggested the employment of carbolic acid for the piupose of keeping sterile the hands of the operator, the skin of the patient, the surface of the woimd, and the instruments used. He finally concluded every operation by a protective dressing to exclude the entrance of germs at a subsequent period.

Listerism, or *' antisepsis," originated in 1875, and when Koch published his famous work on the '*Wimdinfectionskrankheiten" (traumatic infectious diseases), in 1878, it spread slowly at first, but surely in the end, to all departments of surgery and obstetrics.

From time to time, as the need /or them was realized, the genius of investigators provided new devices which materially aided in their work, and have made possible many discoveries that must otherwise have failed. Among them may be mentioned the improvement of the compound microscope, the use of sterilized culture fluids by Pasteur, the introduction of solid culture media and the isolation methods by Koch, the use of the cotton plug by Schroeder and van Dusch, and the introduction of the anilin dyes by Weigert.

It is interesting to note that after the discovery of the anthrax bacillus by PoUender and Davaine, in 1849, there * Agnew's " Surgery," vol. i, chap. ii.

was a period of nearly twenty-five years during which no important pathogenic organisms were discovered, but during which technical methods were being elaborated, making possible a rapid succession of subsequent important discoveries.

Thus; in 1873, Obermeier discovered Spirillum obermeieri of relapsing fever.

In 1879 Hansen anuQunced the discovery of bacilli in the cells of leprous nodides, and Neisser discovered the gonococcus.

In 1880 the bacillus of typhoid fever was observed by Eberth and independently by Koch, Pasteur published his work upon ** Chicken-cholera," and Sternberg described the pneumococcus, calling it Micrococcus pasteuri.

In 1882 Koch made himself immortal by his discovery of and work upon the tubercle bacillus, and in the same year Pasteur published a work upon '*Rouget du Pore," and Lofiler and Shiitz discovered the bacillus of glanders.

In 1884 Koch reported the discovery of the ** comma bacillus," the cause of cholera, and in the same year Loffler isolated the diphtheria bacillus, and Nicolaier the tetanus bacillus.

In 1892 Canon and PfeiflFer discovered the bacillus of influenza.

In 1894 Yersin and Kitasato independently isolated the bacillus causing the bubonic plague then prevalent at Hong-kong.

A new era in bacteriology, and probably the most tritunphant achievement of scientific medicine, was inaugurated when, in 1890, Behring explained to the world the principles of the '* blood-serum therapy."

Chapter I. Bacteria*

Definition. — Bacteria (from the Greek fiaxnjptov, a rod) are minute unicellular organisms, now generally conceded to belong to the vegetable kingdom and classed among the lowest thallophytes.

Classification of Bacteria. — ^The bacteria were thought by Leeuwenhoek and his successors, even to the time of Ehrenberg and Dujardin, to be animalcules belonging to the infusoria, and were in consequence placed in the animal kingdom. With our present knowledge they can imhesitatingly be placed in the vegetable kingdom, among the lower orders of the flowerless plants. The flowerless plants or Cryptogamia include the Pteridophytce; the BryophyUEy including the ferns and liverworts; and the Thallophytce, including the algcB and fungi. It is, therefore, among the Thallophytae, and probably among the fungi, that bacteria belong.

The algae differ from the fungi in possessing chlorophyl. As the bacteria sometimes contain chlorophyl, it becomes a question whether they should be included in either of these groups or form a group by themselves; and their classification among the fimgi is held by botanists to be purely provisional.

The scientific grouping of the bacteria themselves has not yet been achieved, the best characters to be used as the basis of classification being undecided. The best system for their provisional arrangement is probably that of Migula,* or the modification of it suggested by F. D. Chester, f in which the morphology, sporulation, and appendages of the bacteria all enter as important features.

* "Sjrstem der Bakterien," Jena, 1897-1900 (vols, i and n appearing at different times).

t "Preliminary Arrangement of the Species of the Genus Bacterium," "Ninth Annual Report of the Delaware College Agricultural Experiment Station," 1897; Newark, Delaware, U. S. A.

BACTERIA.

1. Family CoccACEiB. Cells globular, becoming slightly elongate

before division. Division in one, two, or three directions of space. Formation of endospores very rare.

(A) Without flagella.

1. Slreptococcus. Division in one direction of space, producing

cnains like strings of beads.

2. Micrococcus. Division in two directions of space, so that

tetrads are often formed.

3. Sarcina, Division in three directions of space, leading to the

formation of bale-like packages.

(B) With flagella.

1 . Planococcus, Division in two directions of space, like micro-

coccus.

2. Planosarctna. Division in three directions, like sarcina.

2. Family BACTERiACBiE. Cells more or less elongate, cylindric, and

straight. They never form spiral windings. Division in one direction of space only, transverse to the long axis of the cell.

(A) Without flagella.

1. Bacterium. Occasional endospores.

(B) With flagella.

2. Bacillus, Flagella arising from any part of the surface.

Endospore-formation common.

3. Pseudomonas. Flagella attached only at the ends of the cell.

Endospores very rare.

3. Family SPiRiLLACBiS. Cells twisted spirally like a corkscrew, or

representing sections of the spiral. Division only transverse to the long diameter.

1. Spirosoma. Rigid; without flagella.

2. Microspira. Rigid; having one, two, or three undulating

flagella at the ends.

3. Spirillum. Rigid ; having from five to twenty curved or un-

dulating flagella at the ends.

4. SpirochcEta. Serpentine and flexible. Flagella not observed ;

probably swim by means of an undulating membrane.

4. Family MYCOBACTERiACBiE. Cells forming long or short cylindric

filaments, often clavate-cuneate or irregular in form, and at times showing true or false branchings. No endospores, but formation of gonidia-like bodies due to segmentation of the cells. No flagella. Division at right angles to the axis of rod in filament. Filaments not surrounded by a sheath as in Chlamydobacteriaces.

1. Mycobacterium. Cells in their ordinary form, short cylindric

rods often bent and irregularly cuneate. At times Yshaped forms or longer filaments with true branchings may produce short coccoid elements, perhaps gonidia. (This genus includes the Corynebacterium of Lehmann- Neumann.) No flagella.

2. Actinomyces. Cells in their ordinary form as long branched

filaments; growth coherent, dry or crumpled. Produce gonidia-Hke bodies. Cultures generally have a moldy appearance, due to the development of aerial hyphae. No flagella.

5. Family CHLAMYDOBACTBRiACBiE. Forms that vary in diff'erent

stages of their development, but all characterized by a surrounding sheath about both branched and unbranched threads. Division transverse to the length of the filaments.

Structure 29

1. Cladotkrix. Characterized by pseudo-dichotomous branch-

ings. Division only transverse. Multiplication by the separation of whole branches. Transplantation by means of polar flagellated swarm-spores.

2. Crenothrix. Cells united to form unbranched threads which

in the beginning divide transversely. Later the cells divide in all three directions of space. The products of final division become spheric, and serve as reproductive elements.