Typhoid Fever-Its Preventable Causes. The gases passing off from sewers have been supposed to possess infective properties, and, in popular opinion, play a large part in disease production. It is clear that there must be a revision of beliefs to conform to existing facts. That sewers give off offensive gases compounds of hydrogen with carbon, sulphur and phosphorous—is entirely true, and that the prolonged breathing of such gases, and the diminished supply of oxygen thereby occasioned, have ill effects on health, cannot be disputed, but specific diseases are not thus produced. The real effects of such gases consist in deterioration of the blood, and of the nutrition in general, and consequently, derangement of the functions dependent thereon; but such a complexus does not agree with the symptoms of some specific or special malady. It is a morbid state, not Typhoid, not Yellow Fever, not Pneumonia; but the way to the development of some special malady is prepared thereby-facilitated by the fermentative decompositions continually taking place. That the action of sewer gas and other gases of decomposition is promotive of disease by lowering the general vitality of a population, may be regarded as probable. The reason for such conclusion is found in the state of the gland patches, and solitary glands of the small bowel under such conditions: They become rather prominent, softened, and are prepared to ulcerate by reason of an over-production of their excretion pressing on their retaining envelope. This must be regarded as a state favorable to the reception of those microbes whose favorite habitat is in these glands, or whose nidus they readily become. That sewer gas does not produce Typhoid is therefore certain, but that the conditions produced by sewer gas favor the growth and development of the parasitic organism of Typhoid may be regarded as true. We have practical illustration and proof of the views above expressed regarding the pathogenic character of sewer gas. ParentDuchatelet, an eminent French sanitarian, has given the figures to show the effects on health of the occupation of sewer cleaning. He finds that the men engaged every day in traversing the great sewers of Paris do not suffer with affections peculiar to their employment, and that their standard of sanitary condition is quite equal to that Typhoid Fever-Its Preventable Causes. of persons of corresponding age, and of occupations not unsanitary in their environment, whence it follows that sewer gas is not so actively toxic as is generally supposed, and that a special disease is not produced by its action on the human body. We may conceive that its more active toxicity in the case of city people is due to their lowered vitality when exposed, and hence that other morbid influences are concerned with it. The question of sewer-gas poisoning must be regarded from another point of view. Although sewer gas cannot of itself cause Typhoid, it may well be believed that in the upward rush of gas and vapor from water pipes having sewer attachments, disease germs may be carried along, and it may thus happen that Typhoid germs are conveyed into a house through the sewer communications. No one observing a street sewer inlet on a cold morning can doubt the realty of this mode of transmitting germs; but that infection often happens in this way is hardly credible, since the organic matter to which they are adherent or in which they are imbedded, must largely prevent this mechanical action of the gases. The number of cases of Typhoid in a given locality where it has appeared from time to time, and the occurrence and severity of epidemics are influenced by some causes, the character of which cannot be determined accurately. The causes in question are largely climatic and physical, and have to do with the development of the Typhoid germ. It has been observed that the amount of rain-fall and the state of the streams and rivers affect the number and pathogenic activity of the germs, probably by the amount of organic matter reaching the potable waters. When the water supply is low, Typhoid increases; when high, decreases. This fact has been established for Munich, certainly, and is in the main true of this country, with some limitations to be presently stated. In and soon after periods of drought, we find that cases of Typhoid become more numerous, but when the rivers are persistently high the number of cases grow smaller. When the water supply is low the relative proportion of organic matter is greater, but when in the course of a prolonged drought, small rain-falls of sudden and considerable force happen, the rushing waters carry the accumulating organic matter Typhoid Fever-Its Preventable Causes. in more or less active decomposition into the water-courses and hence a considerable increase in the amount of this matter must take place for the time being. Restricted rain areas in a defined water-shed may thus add quantities of decomposing matter to the water supply of communities so situated as to be dependent on the supply coming from such districts. In referring an increase of Typhoid to the lowered water supply, such conditions as localized rain areas must be taken into account. Beside an increase in the activity of germs, it must also be remembered that the rain flood will carry with it any germs newly added to the soil or surface water. The relation of the potable waters to the number of Typhoid cases, as set forth above, should not be confounded with the "Ground-water" [Grundwasser] theory of Pettenkofer, the celebrated Munich sanitarian. He holds that the rise and fall of the ground-water [surface water] has an intimate relation to various epidemics, especially of Cholera: As first put forward by the Munich sanitarians, Buhl especially, the statement that Typhoid Fever flourishes when the surface waters are low, is affirmed to be a fact in respect to the epidemics of that locality, but is not proposed as a working theory for general application. The manner in which the decomposition or ordure, and the influence of human excretions generally affect man has been sufficiently set forth. It should be considered further how climatic influences act on these processes, to promote or retard them, to favor or prevent the development of the Typhoid germ. The mean annual isothermal, isochimenal and isotheral lines have little influence over the genesis of Typhoid. In Norway and Sweden, in the most northern of the provinces, in Finland, in European Russia, up to the latitude of the permanent snow-line, Typhoid levies its tolls on the human race. In the most southern parts of Portugal and Spain it is equally at home, nor does it spare the most beautiful islands of the Mediterranean. On this side of the ocean, cases occur from Labrador to the Central American States, and as far as Montevideo. Severe epidemics have occurred in the coldest parts of Siberia and Finland. These facts indicate the powerful viability Typhoid Fever-Its Preventable Causes. of the germ, as has been set forth, and also prove that the mere decomposition of animal excretions cannot produce it de novo — a conclusion arrived at by independent examination of other data. Beside the influence of age in modifying certain anatomical structures, referred to in another place, age has also some effect in lessening or increasing the susceptibility to the action of the Typhoid germ. The greatest number of cases occur between the ages of twenty and thirty years. This decennium has twice the number of victims compared with those nearest in age, according to the estimate of the best medical statisticians. Or to state the same fact in another form: from the ages of fifteen to thirty there are eighty per cent of the whole number of cases. The relative proportions decline from the period of fifteen to thirty in both directions. Hence it may be said that the susceptiblity to Typhoid is the greater the nearer the age to the most vigorous period of life. The same principle holds in regard to sex: men are more liable than women, but the difference is not very great. Other diseases lessen the proneness to attacks: pregnant women are almost, but not entirely exempt, and chronic diseases that keep the bodily strength at a low point exercise some protective influence, and lessen the susceptibility. These modifying influences must not be confounded with morbid states that increase the gravity of Typhoid when it does occur in the subjects of such conditions. Thus, Chickahominy Fever, a Typhoid occurring in soldiers whose tissues were depraved by evil personal and camp hygiene, had the more of a destructive character, because their constitution forces had been undermined by the composite toxic influences in question. As the occurrence of Typhoid procures immunity to a less or greater extent from future seizures, it is classed among the specific infections, with the eruptive fevers as Measles, Scarlet Fever and others, having the property to so impress the system that no subsequent exposure will cause a recurrence; but it does not have the same degree of power to exempt as those named. It is not common to find a second case in the same individual; but by no means unprecedented. The reason for exemption in a partial degree is Typhoid Fever-Its Preventable Causes. probably the changes which were made in the glands of the intestine when the first infective microbes began their growth about and in them. CONCLUDING OBSERVATIONS. If the data above set forth are based on a true estimate of the conditions which have to do with the development of Typhoid, and there can be no doubt as to the accuracy of the statements, the means and methods by which the occurrence of the fever may be restrained or prevented follow as a necessary consequence. A correct summary of the conclusions reached will make more clear the nature of the methods which should be utilized for this purpose. Typhoid is a separate and distinct morbid entity-a specific [in general sense] disease, self-limited, and always conforming in its essential characteristics to the original model. Its cause is a disease germ-a microbe or micro-organism-which reaches man by air, or food, or drink. When in the intestine, coming to the lower end of the ilium, or small bowel, it finds in the glands situated there its proper pabulum -or food suitable to its growth. The disturbances of the human system [the symptom-complexus] which we call Typhoid Fever, is caused by the injury done at the point where the growth and reproduction of the parasite are going on, namely, in the groups of glands imbedded in the mucous membrane there, called "Peyer's patches," and also in the solitary glands and other organs; or by the production of some poison which, entering the system, causes all the symptoms of the fever. The latter the peculiar poison produced by these microbes—may be the more probable, because by a similar process as Dr. Vaughan has proved, Tyrotoxicon is produced, and this poison acts on the human system in a way identical with Cholera Infantum. Whether the direct effect of the changes induced in important excretory glands, or of a poison generated by them, it is certain that the presence of these parasites is necessary to the result. The multiplying germs are found in the stools of Typhoid Fever, and not only organisms complete in their development, but spores |