MORTALITY AND MORBIDITY IN INFANCY According to the tables, the mortality is very high in the first year, is at its minimum from the tenth to the fifteenth year, and increases in the succeeding decades, at first slowly, and later more rapidly. This may easily be seen from figures taken from the German Table of Mor tality of 1871—S1 (Table 1) and from the curve (Fig. 17).
The mortality during the first year is by no means uniform. A calcu lation in the Berlin Statistics of 1S93-1S97 (Westergaard) gave the figures shown in the diagram (Fig. 1s). The death rate, high in the first month, falls rapidly at first, and then falls more and more slowly. Of 100,000 children of the respective ages the average daily mortality was: A more minute analysis of the mortality during the first month, distinguishing boys and girls and between legitimate and illegitimate children, yields the figures in Table 2. From these it may be seen that the mortality of boys is greater than that of girls and that the mortality of illegitimate children is almost double that of legitimate.
The above figures, showing the high mortality of children during the first year, have been taken from German statistics, but the same phenomena appear everywhere. though in varying degrees. We adduce as proof of this a table calculated by F. Prinzing, in which the mortality of children in the different European countries is compared (percentage of children who die in their first, year, omitting the still-born). Beside this we tabulate the number born per IMO inhabitants, the number of these that survive their first year, and the number that die after their first year and before the expiration of their fifth (Table 3). It 11lay easily be seen from this table that the effect of infant mortality on popula tion depends partly on the ratio of births. In France, for example, in spite of the low death rate among infants, the number of survivors is not so great as in Germany, because the number of births is smaller. The table also shows that it is an error to believe that a high death rate among infants is advantageous because it eliminates the weak. Coun tries with a low mortality in the first year usually have also a low mor tality among children between one and six years old.
We see by Prinzing's tables that during the last century there Las been a considerable decrease in infant mortality in Switzerland, Holland, Italy, Finland, Sweden, and Norway. In the other European countries
the fluctuations are slight. An increase in the middle of the nineteenth century was followed by a decrease, which in Austria was permanent. In Belgium, Great Britain, and Ireland an increase was visible in 'SSG 1S96. France, Denmark, and Russia have, in the last two decades of the century, shown a uniformly high ratio.
In the different sections of Germany, infant mortality varied greatly. From 1871 to 1S75 there was a marked decrease in the South, accom panied by a far greater stability in the North. It is significant that in Prussia a decline in mortality was shown for all except infants. This must he attributed to the improvement in hygienic methods and in the standard of living among the poorer classes, effected by social legis lation. This decline is made apparent in a table by Kruse, which is here given in part. In the last quarter of a century the mortality of infants has remained almost constant, while the mortality of older persons has decreased nearly one-half.
Under such circumstances, infant mortality demands special atten tion. We must first of all determine what diseases occasion the heavy mortality of the first year. In the following diagram (Fig. t9) we may find the most important diseases, according to the German statistics for 1900, and will see that, for every 1000 births, 225 deaths occurred in the first year. Of these 223 deaths, S4, or more than one-third, were caused by stomach or bowel troubles. Diphtheria and croup, whooping-cough, measles, and scarlet fever, together, account for only one-twentieth of the entire mortality; and tuberculosis, inflammation of the lungs, and other inflammatory ailments of the respiratory organs, for about one tenth. This prominence of the stomach and bowel troubles may be exhibited in another way. Fig. 20 shows, according to the Hamburg statistics of 1904, (I) the actual number of weekly deaths, (II) the deaths of children in their first year. (III) the deaths by diarrhwa and cholera, and (IV) the deaths from acute ailments of time respiratory organs. Front this diagram it is evident that the general mortality for the year is determined by time infant mortality. and this, in turn. by the number of deaths arising from diseases of the digestive organs. The inverse mortality curve of the more or less numerous diseases of the respiratory organs (curve IV cannot materially affect the general result.