I have included, as of great value and directly related to the epidemiologic phase of this study, reports of some of the bacteriologic work done in connection with this epidemic at the Bureau of Science, Manila, by Dr. Otto Schöbl. I am sure that the value of his studies as reported in part here, with his permission, will be apparent to every careful reader. I am greatly indebted to him for his permission to make use of this portion of his studies. Having been in daily touch with Dr. Schöbl during the year and a half of the continuance of this epidemic, I can appreciate to the fullest extent the painstaking and accurate character of his work and findings, of which the part here presented is by no means the greatest.
I am quite aware of the fact that there are those who view with some question the practicability of controlling plague by the measures applied in Manila, as recited here; but American plague workers are likely to meet this unbelief by pointing to the accomplished fact, in San Francisco, in Honolulu, in Porto Rico, as well as in Manila; and before long, as we confidently expect, in New Orleans.
These exponents of the school which contends that plague epidemics are little affected by rat-excluding, rat-destroying and rat-proofing efforts, believe that the waning and disappearance of epidemic plague in a given place depend in chief part upon the exhaustion of susceptible material among the rodent population. However appealing this argument may be, it is impossible for its exponents to duplicate American results with equal results in the cities of China, India, Java and elsewhere, where governmental control and adequate financial ability to carry out campaigns have been lacking, from one cause or another. Wherever our methods have been followed, at home and in the insular possessions of the United States, we have terminated human epidemics of plague and have apparently put an end to rat plague in comparatively short campaigns. So long as this discrepancy in results continues we shall favor the American plan. When we review the work and results of Blue and his fellows of the United States Health Service and the officers of the Bureau of Health of the Philippine Islands, we find little reason for us to favor a change to the expectant plan of waiting for an epidemic to run its course.
While speaking of the Philippine Islands, the admirable work of Strong in Manila, covering years of study of the immunity problem, and his dangerous and highly valuable work as a member of the Commission which studied the Manchurian epidemic of pneumonic plague in 1911, must be mentioned.
Some years ago I called attention to the fact that few, if any, American cities were prepared to meet an outbreak of plague with an adequate supply of antipest serum and that the preparation of antiplague serum was a neglected or overlooked branch of serum manufacture in the United States. Since that time, in the midst of a plague epidemic in Manila, where, for a time, the supply of locally prepared (Bureau of Science) serum threatened to become exhausted, I looked into the possibilities of getting a supply elsewhere and found that, to do so, in anything like a reasonable length of time, was impossible. Fortunately the threatened serum famine did not occur, the local supply in Manila proving adequate, although for a few weeks we were obliged to make use of a stock of Japanese serum which had been on hand for several years. Since the warning of some years ago, at which time the plague danger was an anticipated one, bubonic plague has actually appeared in the United States (New Orleans), the cases being sufficiently numerous to cause grave concern and to call forth the utmost repressive efforts of the authorities. The possibility of plague appearance in the coast cities of the United States, at any time, cannot be disregarded and provision for the treatment of human cases, as well as repressive (antirat) measures, is imperative. Antiplague serum is not producible upon a few hours' notice, nor is it manufactured in the United States. In view of present war conditions the difficulty of securing serum from overseas sources is greatly increased, so that we are well-nigh compelled to depend upon home-produced serum. In view of the uselessness of drug treatment it is plainly the duty of national, state and municipal authorities to keep on hand a reasonable supply of antipest serum to meet any outbreak. Manufacturers of biological products realize that the preparations for producing, storing and marketing antiplague serum are expensive and that the maintenance of immunized animals and the employment of expert serologists call for expenditures which are unlikely to be recovered from any demand for serum and that, moreover, the government is doing and will do all that lies within its power to make the serum unnecessary, by excluding plague. These are not encouraging conditions to lead American serum producers to add antiplague serum to the list of their products. If, under these adverse conditions, any producer of biologic products shall undertake to produce and maintain an adequate supply of antiplague serum, he will merit credit for a truly philanthropic service and will deserve the support of governments, national, state and municipal, as well as that of the medical profession.
[CHAPTER I
ITS HISTORY AND ITS EXTENSION]
In plague there exists the most intimate relationship between cause and prevention. We will therefore set forth here, as briefly and concisely as their importance will permit, the principal facts related to the causation of the disease. Without an understanding of this relationship there can be no rational preventive treatment.
These facts constitute one of the interesting stories of modern medicine: the story of the arrangement and interpretation of certain apparently unrelated facts, some of them long known to men, in the clear light of modern method; the story of the application of analysis, synthesis, logic and experiment, all leading to the creation of an understanding which permits us to battle successfully with pestis bubonica, one of the most ancient of human plagues.