A system of practical medicine. By American authors. Vol. 1

by Unknown

Sex does not exert any definite or constant influence upon the mortality. The number of males affected is far greater; they are liable to be exposed to the contagion in its most concentrated form; a larger proportion of them are probably the subjects of intemperance than in the case of females; and thus most statistics agree in making the mortality somewhat greater in the male sex; but, all things being equal, there is no good reason for holding that sex itself has any value in determining the result.

As in other zymotic diseases, the mortality from relapsing fever is highest during the early period of an epidemic, and the type of the disease grows milder as the epidemic declines. Cases of the bilious typhoid form have become notably less frequent during the later stages of some epidemics than at an earlier period.

Marked difference has been observed also as to the action of remedies at different stages of epidemics, the early cases exhibiting an extraordinary resistance to remedies, and especially to anodynes, which passes away later. When typhus and relapsing fevers have prevailed together, and a clear discrimination between the two sets of cases has not been made, it has appeared that the mortality increased as the epidemic advanced, but this apparent exception has been due to the fact that at first the cases of relapsing fever were in the majority, while later those of typhus, the much more fatal disease, preponderated.

Epidemics of relapsing fever prevail at all seasons, but more commonly they are at their height during the colder months of the year. The total mortality will of course correspond, but the actual percentage is not constantly greater during any one season, although it is probable that the greater liability to chest complications during the colder months will render the disease more fatal then.

The gravity of relapsing fever has varied so greatly in different epidemics that it is very difficult to determine what influence upon the mortality has been exerted by mere difference of race. A further source of difficulty is found in estimating the differences in the physical conditions of the poorer classes in the various communities affected. The mortality has been exceptionally high in the Russian and Indian epidemics and in some of the German ones, while in the British epidemics it has uniformly been light. It is interesting to note that in the Philadelphia epidemic, where the great majority of patients were Irish or negroes, the mortality was high, over 14 per cent. The previous condition of the Irish patients must certainly have contrasted favorably with that of the individuals attacked in the Dublin and Belfast epidemics, so that the difference in result seems attributable only to a greater virulence of the disease. As an ample opportunity was here afforded to judge of the relative severity of relapsing fever in the negro and white races when the cases occurred at the same season, at the same stage of the epidemic, and in individuals living under nearly similar conditions, it may be stated that the conclusion of all who studied the question closely was that the disease was much more severe among negroes, and in particular that they displayed a greater tendency to serious complications and to the bilious typhoid form.

Although the degree and virulence of the infection undoubtedly constitute the most important elements in determining the mortality, the previous health and habits of those attacked with relapsing fever exert an influence upon the result. This is especially true of habitual intemperance, which, by disposing to disease of the liver and kidneys, greatly increases the liability to a fatal result. It has been seen ([above]), however, that even when acute catarrhal nephritis existed at the time of the attack severe relapsing fever might terminate favorably. Another observation which we made frequently, and which coincides with what is well known in regard to typhoid and typhus, is that improper exertion and exposure during the stage of incubation and immediately after the invasion produced a highly unfavorable effect on the subsequent course of the disease, and seemed in particular to dispose to dangerous or fatal collapse at the critical periods.

Apart from these general considerations, there are many special points to be considered in regard to the prognosis of relapsing fever:

If after the crisis of the invasion there is not rapid and decided improvement, complications should be suspected.

A sharp rebound of temperature quickly following crisis may be followed by speedy death.

Mere elevation of temperature during the invasion and the relapse, even though to an extreme height, is not attended with the danger which even a somewhat lower degree would indicate in other zymotic diseases.