THE INFLUENCE OF ACUTE ALCOHOLISM ON THE NORMAL VITAL RESISTANCE OF RABBITS TO INFECTION.

By A. C. ABBOTT, M. D.,

FIRST ASSISTANT, LABORATORY OF HYGIENE,

UNIVERSITY OF PENNSYLVANIA.

THE INFLUENCE OF ACUTE ALCOHOLISM ON THE NORMAL VITAL RESISTANCE OF RABBITS TO INFECTION.1

IN the distribution of the several subdivisions of the general question relating to the influence of alcohol upon the physical and moral well-being of those who use it as a beverage, the Committee saw proper to assign to Dr. Abbott for experimental solution the question concerning the influence of alcoholism, acute and chronic, upon the normal vital resistance of animals to various forms of infection.

At the beginning of the work a general scheme of procedure was drawn up that seemed to meet most of the requirements of the problem, but it was found possible to cover only a limited portion of the ground included in this scheme within the time allotted to the investigation.

The lines along which it was proposed to conduct these investigations are as follows:

1. Determine if the normal vital resistance of animals to infection by the common pathogenic bacteria is demonstrably influenced by either acute or chronic alcoholism, induced through the use of known amounts of pure ethyl alcohol.

2. If any or no effect is observed, determine if the same holds. good for animals under the influence of the commoner alcoholic beverages, as beer, wine, whiskey, cordials, etc.

3. Determine if through either acute or chronic alcoholism the germicidal properties of the serum of the blood of animals. is materially altered. If so, determine, if possible, the nature of this alteration.

1 Abstract of a paper which appeared in vol. i., 1896, of the Journal of Experimental Medicine.

Investigations bearing upon paragraph 3 have been conducted independently by Dr. Abbott and Dr. Bergey, of the University of Pennsylvania, and published under the title, "The Influence of Alcoholic Intoxication upon certain factors concerned in the Phenomenon of Hæmolysis," in the August

The results presented in this paper refer only to the influence of acute alcoholism upon the resistance of rabbits to infection by the pyogenic cocci - i. e. the streptococcus pyogenes (erysi pelatos) and the staphylococcus pyogenes aureus — and by the bacillus coli communis. They are in many ways sufficiently instructive to warrant their publication.

The following abstract will serve to present in general the lines along which the study was projected and the results obtained. The details are given in full in the original paper.

A difficulty that arose at the outset was in procuring cultures of pathogenic organisms of suitably diminished virulence without their being at the same time totally devoid of this property. As experience has taught us to expect certain deviations from the usual course of infection when normal animals are inoculated with attenuated cultures, such, for instance, as prolongation of the period of incubation and modification of the pathological lesions, the problem under consideration seemed to be in part most easy of solution through a comparison of results ob

and September number of the University of Pennsylvania Medical Bulletin for 1902.

The points considered by the authors in this paper were :—

1. Does alcohol administered per os influence the complement content (Ehrlich's nomenclature) of the blood of rabbits?

2. Does alcohol similarly administered have an influence upon the specific blood reactions of rabbits already artificially immunized against an alien blood?

3. Does alcohol similarly administered have any influence upon the process of artificial immunization by an alien blood?

The results of studies upon these three questions seem to warrant the following conclusions:

1. The daily administration of alcohol per os to rabbits brings about a reduction in their circulating blood of the hemolytic complement.

2. Slight alterations in the normal alkalinity of the blood serum have no demonstrable influence upon the (hæmolytic) complement of the blood of alcoholized rabbits.

3. The diminished reactivating power of the blood of alcoholized rabbits is not due to the presence of small amounts of alcohol as such in the blood. 4. The administration of alcohol to rabbits induces not only a marked reduction in the complement content of their blood, but may cause, at the same time, a reduction in the specific haemolytic receptor in the blood of rabbits artificially immunized against an alien blood.

5. The diminished complement content of the blood of alcoholized rabbits renders the animal more susceptible to the toxic action by an alien blood.

tained by the use of such cultures on groups of alcoholized and non-alcoholized animals. Should such modifications occur in the normal animals as would be anticipated, and an infection not differing from that produced by fully virulent cultures occur in the alcoholized animals, the difference could reasonably be referred to a reduction of vital resistance brought about by the alcohol administered.

To meet the requirements it would perhaps have been best to have employed cultures of organisms that were diminished in virulence to definite degrees of attenuation, such, for instance, as the bacillus anthracis attenuated to the degree of virulence represented by its primary and secondary vaccines. As such material was not available, however, cultures of another sort were used, namely, those that were of a low degree of virulence without this degree being definitely determined.

Again, cultures of organisms were employed, the pathogenic powers of which are usually irregular and uncertain; while in still other tests an effort was made to detect a difference between alcoholized and non-alcoholized animals when inoculated with virulent material, but in very small doses, hoping in this way to demonstrate, by a difference in the period of incubation, a difference of resistance in the animals composing the two groups.

The experiments were made with cultures of streptococcus pyogenes of a low degree of virulence, with normal baccillus coli communis, and with virulent staphylococcus pyogenes aureus, and, as the results to be reported show, with very diverse consequences.

Another difficulty was encountered in regulating the dose of alcohol. The intention was to have the animals daily in a state of intoxication, but it is not easy to decide just when this stage is reached, as the only certain indication of it is inco-ordination of muscular movement. It frequently occurred that when alcohol was given to this stage, the direct effect of the drug was such as gravely to imperil the life of the animal, and in a certain number of instances the animals did not rally from even so few as one or two such administrations. If the dose were diminished, then one could often not be sure that the rabbit was intoxicated.

On the other hand, one encounters occasionally an individual