CHAPTER XXIX.

THE COURSE, DURATION AND MORTALITY OF CHOLERA.

THE course of cholera has been amply illustrated in the foregoing, so that it seems scarcely necessary to again consider it here. But it will be interesting and instructive to examine some statistical evidence, more particularly as regards the mortality of the disease. This will further elucidate the course and duration of the disease, and thus justify the title placed at the head of the chapter.

As has been previously pointed out, the death-rate from cholera is a very variable one. Not only do different epidemics show variations that are found equally extreme in no other disease, but the same epidemic has a mortality-rate that is constantly changing. One fact, however, has been universally observed, namely, that the early history of an epidemic is associated with the largest number of victims, and that there is a tendency to gradual mitigation even while the disease may continue to spread. The wide territorial extent of an epidemic is not necessarily coupled with a high degree of mortality. If anything, the death-rate diminishes, so that places reached late may suffer but little, as if the virulence of the infecting agent had become exhausted in traveling long distances. For this reason we should have less dread of the disease in our own country than may be reasonably felt abroad. And if the partially exhausted poison reaching our shores is not called back to renewed life and malignant potency by finding favorable conditions for further development in the accumulated dirt and refuse of large cities, then we may forever hope to escape the horrors and panic of a largely fatal epidemic. The recent Parisian outbreak (1884) affords a good illustration of the peculiarity just mentioned.

Cholera after ravaging Southern France, Italy, and Spain, at length appeared in the French capital. But being already rather exhausted with its long travels, and meeting with little encouragement in the way of dirt, water-contamination and other unhygienic conditions, it was quickly sup

pressed.

Some early epidemics are reported to have killed only 5 per cent. of those attacked. This seems highly improbable. On the other hand, several more recent outbreaks are positively known to have had a death-rate varying between 70 and 90 per cent. A broad average shows a mortality not far either way from 50 per cent.

The death-rate is evidently influenced in some measure by the geographical situation of a place, increasing as we approach the equator, and diminishing in proportion as we recede from it.

Local causes have a marked bearing on the death-rate. The quality of the soil on which houses are built, the drainage, the hygienic conditions

surrounding the patients, are all influential in causing a high or low mortality.

There appears to be no constant difference in the death rate of general hospitals as compared with private residences. It should be remembered that the "general hospital" cases are recruited from the poorer classes of society, and further that on admission the disease has already made more or less headway. There is no doubt that, general hospitals show a higher death-rate than cholera hospitals. When the disease spreads from a cholera ward to the general wards a high mortality is inevitable. Thus in the epidemic of 1854 Haller found in the Vienna General Hospital a deathrate from cholera of 52 per cent. in the cholera wards, whereas the mortality from the same disease in the general wards rose to 74 per cent., and the same experience was had in the great epidemic of the following year. Leubuscher reports a death-rate of 52.5 per cent. in the cholera hospital of Berlin, at a time (1850) when the general city mortality was 60 per cent. A well-managed cholera hospital is, therefore, calculated to save lives that would ordinarily be sacrificed.

We have just seen that the average run of hospital cases is apt to be more severe than in private practice. But there are compensating circumstances that should not be lost sight of. It is evident that immediate medical interference may in some cases at least, avert the impending fatal issue. Now even with the most intelligent assistance of trained nurses, the general practitioner is clearly placed at a disadvantage, when compared with his hospital confrere, who is ever ready to obey on the instant, the urgent summons of his patients.

In studying the records of mortality statistics, the fact must not be lost sight of that they will vary in accordance with the prevalent medical belief of a country. If during an epidemic the majority of physicians report all cases of diarrhoea as belonging to the category of Asiatic cholera, there will naturally be very many recoveries, and a corresponding decrease in the death-rate results therefrom. If, on the other hand, only the fully pronounced cases are allowed to be cholera, the opposite will take place; i.e., there will seem to be a very high death-rate.

Drasche has made the practical suggestion that the appearance of ricewater dejections be taken as an index of the presence of true cholera. While this may not be pathologically correct, it will nevertheless insure uniformity of reports, and thus enable us to prepare trustworthy statistics,

The valuable monograph of the above writer contains a series of instructive tables that afford a better illustration of the various factors influencing mortality than lengthy descriptions can hope to convey. Several of these tables are here reproduced:

1-10.

11-20.

21-30

31-40.

41-50.

51-60.

61-89.

It is unnecessary to make any comment upon the significance of these figures.

If we turn now to London and examine the official returns of the epidemic of 1854, we will have to read the same lesson:

AGE.

15-25.

25-35.

35-45.

45-55.

55-65.

65-75.

75-85.

66

.45.4

66

62.1 64

66

.76.2"

66

...86.0

66

66

The following table will be found instructive, being based on 1,630 personal observations with careful records made by Drasche in Vienna in the years of 1854 and 1855:

Mortality at the Vienna General Hospital in 1854 and 1855.

The following tables will be found of still greater interest, as presenting an accurate statement of the mortality from cholera and various factors influencing the same, in the United States, during the epidemic of 1873. They are taken from Dr. McClellan's report.'

It is clearly seen from a study of these tables, and, indeed, of all reliable mortality statistics, that the death-rate advances quite steadily with the increasing age of the patients. In Drasche's Vienna Hospital table, an apparently excessive mortality is recorded for the ages from one to twelve years. This is due to the fact that the death-rate of very young children is an extremely high one, and having been included in his computation has resulted in an average that is seemingly above the usual one.

1 Washington, 1875, pp. 34, 35.

Recoveries.

Total...... 137 283 55 2441 323 321712405 73 7746 740 6232134 435 7356

These different tables fairly represent the average mortality, and the death rate as influenced more particularly by the age of patients. With regard to infantile mortality they are not accurate. A large experience of many epidemics has shown that up to and below one year of age, the death-rate is frightfully high-generally above 92 per cent., and often reaching 98 per cent.

In old age the death-rate is likewise very high, but less excessively so than in early infancy.

As a matter of course weak, debauched and cachectic individuals of middle life contribute a far larger proportion of deaths than the strong and robust.

Griesinger calculates that in large cities about half the number of deaths are observed in those at the time or recently sick and ailing. On the other hand, Dr. Gairdner mentions that the post-mortem examinations of choleraics in Edinburgh showed very little disease in the bodies of those who died there.

The lower classes, for easily understood reasons, show a higher rate of mortality than the well-to-do and wealthy.

Occupation plays a rôle in the production of mortality only in so far as debilitating work or unhealthful surroundings may vitiate constitutional vigor. Thus Goodeve found in India that the privates and non-commissioned officers of regiments suffered more than the officers. He says further that fatigue, want, grief, fright, have doubtless some degree of influence, though it would be difficult to estimate how much. Of these he considers fatigue the most injurious.

A study of the general mortality of cholera is made additionally interesting by keeping in view the death-rate of the various periods of the disease. It is singular how scanty are reliable statistical records elucidating these points.

Statistics of Sex, Social Condition and Results of the United States Epidemic

of 1873.

Grand Total. 137 283 55 2 441 323 32 1712 405 73 7 746 740 6232134 435 7356

A table based on 805 cases under the personal observation of Drasche was published by him in 1866, and is here reproduced: Death-rate at Different Periods of an Attack.