The stage of the disease at which efficient treatment is begun has a manifest influence upon the result. This is strikingly shown by some observations of Jackson: 90 cases were admitted into the Massachusetts General Hospital during the first week—of these 7 died, or 1 in 12.85; 139 cases were admitted in the second week—of these 16 died, or 1 in 8.68; 46 cases were admitted in the third week—of these 10 died, or 1 in 4.60; and 21 cases were admitted in the fourth week, and of these 5 died, or 1 in 4.20. Convalescence also occurred much earlier in those who were admitted early.

Murchison found that in a large number of cases the death-rate varied at different ages as follows: Under ten years it was 11.36 per cent.; from ten to fourteen years it was 12.86 per cent.; from fifteen to nineteen years it was 15.48 per cent.; from twenty to twenty-nine years it was 20.46 per cent.; from thirty to thirty-nine years it was 25.90 per cent.; from forty to forty-nine years it was 25 per cent.; and above fifty years it was 34.94 per cent.

According to Liebermeister, among the 1743 patients treated for typhoid fever in the hospital at Basle from 1865 to 1870, inclusive, there were 130 who were more than forty years old; of these 39, or 30 per cent., died, while the mortality among the patients under forty amounted only to 11.8 per cent. Among the cases of typhoid fever in individuals over forty years of age collected by Uhle, more than half proved fatal. According to Friedrich,96 there were, among 16,084 children treated in the Children's Hospital at Dresden, 275 cases of typhoid fever, of which 31, or not quite 11 per cent., proved fatal. Age, therefore, exercises a positive influence upon the mortality of typhoid fever. Its influence is less decided in this disease than in typhus, in which the death-rate does not reach 4 per cent. until after the age of twenty, when it rapidly rises from 12.34 per cent. until it reaches 57.03 per cent. in patients above fifty years of age. The comparatively slight mortality of typhoid fever among children is probably due to the fact that the temperature is less often continuously high in them than in adults, and that while hyperpyrexia is frequently present, it is generally better borne and less likely to produce paralysis of the heart. Liebermeister says that the only case which he has seen recover after the temperature had repeatedly risen to 107.5° F. was that of a girl fourteen years of age. It is also said that the intestinal lesions are not so severe, and the liability to complications and sequelæ less marked, in children.

96 Quoted by Liebermeister.

Typhoid fever appears to be a slightly more fatal disease in women than in men, for while in some local epidemics the percentage of deaths is greater among the latter than among the former, the reverse is found to be the case when the records of a large hospital for a number of years are carefully examined. According to Murchison, the mortality at the London Fever Hospital was about 1 per cent. higher among the female than among the male patients, and about the same difference in the death-rate of the two sexes has been reported by continental physicians. A greater disparity even than this has been observed by Liebermeister at the hospital at Basle, where the death-rate for women was 14.8 per cent., and only 12 per cent. for men. Murchison says that this excess of mortality among the former cannot be accounted for by the influence of child-bearing upon the course of the fever, since it is much more decided between the ages of five and fifteen than in the period of child-bearing.

The rich are not only as liable to contract typhoid fever as the poor, but the disease is also quite as fatal among them. Murchison found from the statistics of the London Fever Hospital that the mortality is not greater among the destitute than among the better class of patients, and expresses the opinion that in private practice enteric fever is probably more fatal among the upper classes than among the very poor. Chomel and Forget seem to have reached a similar conclusion.

All authors agree that the prognosis is unfavorable in corpulent persons, not only on account of the diminished power of resistance to disease generally which such persons exhibit, but also because the febrile movement is often intense in them, and the degenerative changes of the muscles and organs of the body which it induces are generally early developed and of high grade. Liebermeister goes so far as to say that even in the case of ill-nourished, anæmic, or chlorotic individuals the chances for life are better than in the corpulent. Murchison has also expressed the opinion that a large, muscular development is likewise an unfavorable element in prognosis, having seen the strong and robust succumb to the disease oftener than the feeble. The mortality from the disease appears to be greater in certain families than in others. This has been ascribed by some writers to peculiarities of constitution, but it may be due to other causes, as, for instance, difference in the intensity of the poison. The disease is also often very fatal among the intemperate, who usually bear the disease badly in consequence of the presence of various degenerations of one or more of the important organs of the body caused by the excessive indulgence in alcoholic stimulants; paralysis of the heart being not an infrequent cause of death among them.

Certain epidemics have been exceedingly fatal, while in others the percentage of deaths has been very small. There can be no doubt that in most of these cases there has been a difference in the virulence of the poison. Recent residence in an infected locality has been shown by Murchison and other writers to have a decided influence in increasing the fatality of the disease. Second attacks are, on the other hand, usually mild. Some diversity of opinion exists among authors in regard to the effect that pregnancy has upon the course of the disease. Murchison believes that it is a far less formidable complication than is usually thought, while Liebermeister, on the contrary, holds a directly opposite opinion. He also regards the prognosis as unfavorable when the disease occurs in childbed or a short time afterward. Individuals with disease of the heart, emphysema, or bronchial catarrh who contract typhoid fever are said to be more liable to paralysis of the heart than others, hence the existence of these diseases materially diminishes their chances of recovery.

TREATMENT.—Inasmuch as the spread and propagation of typhoid fever may be prevented to a great extent, if not entirely, by the employment of judicious sanitary measures, it is proper, before entering upon the discussion of its curative treatment, to devote a few words to the prophylaxis of the disease.

Whether the physician accepts the theory so ably advocated by Murchison, that typhoid fever may arise from exposure to the products of the fermentation of healthy feces, or adopts the view now held by a large number of investigators, that the disease is never generated in the absence of the specific germ, he will admit the great importance of an efficient system of sewerage, with a thorough flushing of the sewers at regular and frequent intervals, for disposing of the fecal discharges of the population of all towns, no matter how inconsiderable in size. No less important is it that the drains of every dwelling should be well constructed and kept in good order. They should be trapped just before they empty into the sewer, and should be provided with the means of thorough ventilation between the trap and the walls of the house by a free communication with the outer air. The soil-pipe should be carried up three or four feet above the top of the house, and every water-closet, bath-tub, stationary washstand, and sink should have its own separate trap, and none of them should be placed in rooms unprovided with a window or with some other sufficient means of ventilation. Physicians should, as sanitarians, urge upon the authorities of all cities and towns the importance of deriving their water-supply from a source unpolluted by sewerage or by any other substances likely to be deleterious to health. They should also see that when water is stored in a tank inside of a house the overflow pipe does not communicate directly with the drain, since if this is allowed to occur the water may very soon become contaminated with sewer gas, and consequently unfit for internal use.