corresponding previous period the daily averages were as follows: October (1894), 5.4; November, 7.1; December, 7.2; and January (1895), 7.0. The decline from the maximum mortality in October, 1895, to January, 1896, was 49.1 per cent; that from the maximum mortality in December, 1894, to January, 1895, was less than 2 per cent. The average decline from the maximum mortality of each year to each following January during the preceding ten years-1885-1894– was 16.8 per cent, or only about one-third the decline during the period of antitoxin administration.

Between April 1 and December 31, 1896, the DEPARTMENT physicians visited 947 cases of reported diphtheria, of which number 665 were verified, and 644 were treated with antitoxin; of those treated with antitoxin 599 recovered, 40 died and 5 remained under treatment at the close of the year. Among those treated there were 72 intubations, with 6 deaths. During the same period 593 exposed individuals were treated with immunizing doses, and 5 of these were subsequently attacked with diphtheria, but all recovered.

The following tables cover the period between October 1 and December 31, 1896:

1. SUMMARY OF THE WORK OF THE DIPHTHERIA ANTITOXIN CORPS OF THE CHICAGO HEALTH DEPARTMENT:

of these subsequently attacked with diphtheria .
of cases intubated.....

4

55

of intubated cases recovered...

47

Exclusive of 5 cases remaining under treatment at the end of December, the mortality rate was 6.6 per cent. of bacterially verified diphtheria425 recoveries, 30 deaths.

II. RESULTS OF ANTITOXIN TREATMENT IN BACTERIALLY
VERIFIED DIPHTHERIA.

Still under treatment, December 31, 1896: two between 1 and 5 years and one over 10 years, treated on first day of disease; one between 1 and 5 years, treated on second day of disease; one between 5 and 10 years, treated on third day of disease.

III. DEATHS AND DEATH RATES BY DAY OF TREATMENT

Up to the close of 1896, from the beginning of the antitoxin treatment as an organized branch of the DEPARTMENT work, October 5, 1895, there had been appropriated by the City Council and expended through the Antitoxin Corps for services and material in the treatment and prevention of diphtheria, a total of $23 495.22.

Following are the gross figures of the work performed and the results :

Death rate under antitoxin treatment, 6.56 per cent.

Experience shows that the average mortality of diphtheria previous to the introduction of antitoxin was about 35 per cent. of all cases-30 per cent. in hospitals and 40 per cent. in private practice. At this rate (35 per cent.) there would have been 806 deaths among the 2302 cases had not antitoxin been used.

Total number of exposed persons immunized..
Total number of these subsequently attacked with
diphtheria....

2016

14

Experience shows that fully one-half of those exposed, under the conditions which obtained in these 2016 cases, would have been attacked with diphtheria; and of those attacked 352, or 35 per cent. of the 1008, would have died. if not treated with the antitoxin. Only 14 out of the 2016 exposed were attacked and none died.

It is well within bounds to claim a direct saving of at least 1200 lives through the introduction and use of antitoxin in diphtheria by the Chicago HEALTH DEPARTMENT during the last fifteen months

Dr. DRAKE'S second diagram shows in a still more striking manner, and for a period covering twelve years -1885 to 1896 inclusive-the great change wrought by antitoxin in the incidence and mortality of diphtheria.

JAN. FEB. MAR. APR. MAY JUNE JULY AUG. SEPT. OCT. NOV. DEC.

The continuous line and figures show the average number of deaths, by months, per 100 000 of the mean population living between 1885 and 1894. During this period the average annual rate was 10.51 per 100 000.

The dash-and-dot-line and figures show the number of deaths, by months, per 100 000 of the mean population (1 619 226) of 1896. The total diphtheria deaths during the year numbered 956, giving a rate of 5.9 per 100 000 of population, as against the rate of 10.51 during the ten years of the pre-antitoxin treatment.

The remaining line and figures in the diagram show the monthly rate per 100 000 for the year 1895-a transition year, during only a part of which was antitoxin used and therefore not capable of comparison.

It is apparent that if the ten-year pre-antitoxin rate, 10.51 per 100 000 of population, had prevailed during 1896, there would have been a total of 1706 instead of the 956 deaths from diphtheria which occurred last year. This saving of 750 lives of those actually attacked with diphtheria in 1896a reduction of nearly 44 per cent. of the usual diphtheria mortality is attributable to no other cause than the use of antitoxin.

It is doubtful if the city ever expended $23 495.22 more profitably for human health and life.