Second-No burden or cumbersome generators have to be carried out, but the sprinkler and supplies can be carried in an ordinary hand satchel, and with an extra supply bottle enough can be taken at the start for three or four disinfections.

Third-Nothing is destroyed in the houses disinfected, as usually occurred after the old sulphur fumigation.

Fourth-Each room becomes its own source of disinfection.

Fifth-There is no fire or danger from explosions.

Sixth-It does not require hours of waiting on the part of the operator for the solution to evaporate, as is necessary when generators are used. Entire disinfection is made as nearly perfect as can possibly be done; any person can thoroughly disinfect his own house, and it is the belief of the writer that the question of domestic disinfection has been solved.

CHAS. W. BEHм,

Bachnologist Chicago Health Department.

XIX

DISINFECTION AND INDIVIDUAL PROPLYLAXIS

AGAINST INFECTIOUS DISEASES*

(Revised by the Author in 1899)

INTRODUCTION

Definition. We are met at the outset by a difficulty growing out of the fact that the word disinfection, as commonly used, has a very different signification from that to which certain authors would restrict it. Thus, the Committee on Disinfectants of the American Public Health Association defines a disinfectant as "an agent capable of destroying the infective power of infectious materia!.' 991 in the preliminary report of this committee the reasons for restricting the meaning of the word within the limits justified by its etymology, and of our knowledge of the nature of "infectious material," are very clearly stated, as follows:

"The object of disinfection is to prevent the extension of infectious diseases by destroying the specific infectious material which gives rise to them. This is accomplished by the use of disinfectants.

"There can be no partial disinfection of such material: either its infecting power is destroyed, or it is not. In the latter case there is a failure to disinfect. Nor can there be any disinfection in the absence of infectious material.

*

*

*

"Popularly, the term disinfection is used in a much broader sense. Any chemical agent which destroys or masks bad odors, or which arrests putrefactive decomposition, is spoken of as a disinfectant. And in the absence of any infectious disease it is common to speak of disinfecting a foul cesspool, or a bad-smelling stable, or a privy vault.

This popular use of the term has led to much misapprehension, and the agents which have been found to destroy bad odors-deodorizers, —or to arrest putrefactive decomposition-antiseptics have been confidently recommended and extensively used for the destruction of disease germs in the excreta of patients with cholera, typhoid fever, etc.

"The injurious consequences which are likely to result from such misapprehension and misuse of the word disinfectant will be appreciated when it is known that recent researches have demonstrated that many of the agents which have been found useful as deodorizers, or as antiseptics, are entirely without value for the destruction of disease germs.

*Lomb Prize Essay, by George M. Sternberg, M. D., LL.D., surgeon general United States army-reprinted by permission of Dr. C. O. Probst, Columbus, O, Secretary American Public Health Association.

1 The Medical News, Phila., Jan. 24, 1885, p. 87.

"This is true, for example, as regards the sulphate of iron or copperas, a salt which has been extensively used with the idea that it is a valuable disinfectant. As a matter of fact, sulphate of iron in saturated solution does not destroy the vitality of disease germs, or the infecting power of material containing them. This salt is, nevertheless, a very valuable antiseptic, and its low price makes it one of the most available agents for the arrest of putrefactive decomposition in privy vaults, etc.

"Antiseptic agents also exercise a restraining influence upon the development of these germs, and their use during epidemics is to be recommended when masses of organic material in the vicinity of human habitations cannot be completely destroyed, or removed, or disinfected.

"While an antiseptic agent is not necessarily a disinfectant, all disinfectants are antiseptics; for putrefactive decomposition is due to the development of 'germs' of the same class as that to which disease germs belong, and the agents which destroy the latter also destroy the bacteria of putrefaction, when brought in contact with them in sufficient quantity, or restrain their development when present in smaller amounts.

"A large number of proprietary 'disinfectants' so called, which are in the market, are simply deodorizers or antiseptics of greater or less value, and are entirely untrustworthy for disinfecting purposes.

991

The offensive gases given off from decomposing organic material are no doubt injurious to health; and the same is true, even to a greater extent, of the more complex products known as płomaines, which are a product of the vital-physiological-processes attending the growth of the bacteria of putrefaction and allied organisms. It is therefore desirable that these products should be destroyed; and, as a matter of fact, they are neutralized by some of the agents which we recognize as disinfectants, in accordance with the strict definition of the term. But they are also neutralized by other agents -deodorants-which cannot be relied upon for disinfecting purposes, and by disinfectants, properly so called, in amounts inadequate for the accomplishment of disinfection. Their formation may also be prevented by the use of antiseptics. From our point of view the destruction of sulphureted hydrogen, of ammonia, or even of the more poisonous ptomaines, in a privy vault, is no more disinfection than is the chemical decomposition of the same substances in a chemist's laboratory. The same is true as regards all of the bad-smelling and little known products of decomposition. None of these are infectious material," in the sense in which we use these words; that is, they do not, so far as we know, give rise directly to any infectious disease. Indirectly they are concerned in the extension of the epidemic "filth diseases," such as cholera, yellow fever, and of the fatal endemic filth diseases, such as typhoid fever and diphtheria, which in the long run claim more victims than do the pestilential maladies first named. This because persons exposed to the foul emanations from sewers, privy vaults, and other receptacles of filth, have their vital resisting power lowered by the continued respiration of an atmosphere contaminated with these poisonous gases, and are liable to become the victims of any infectious disease to which they may be exposed. Moreover, the accumulations of filth which give off these offensive gases furnish pabulum upon which certain disease germs thrive; and it may happen that the bad smelling air 1 The Medical News, Apr. 18, 1885, p. 425.