Judging from recent medical text books it is evident that medical writers are generally accepting this view as the proper one. At any rate, my experiences and those of my medical friends during the Manila epidemic of 1912–1914, have led me to discard as impracticable, unproven, disproven or unpromising, certain plans of treatment formerly deemed worthy of trial. I do not refer to these methods individually but will content myself, instead, with reciting briefly the methods which I believe, from personal experience and the collected experience of others, to be worthy of continuance and of further trial.
Diagnosis.—The rapid diagnosis of plague is always of the utmost importance, both from the view-point of prognosis and treatment, in the individual case, and from the community view-point of the recognition of the presence of a dangerous communicable disease, with the resultant obligation falling upon the health authorities.
The Biologic Diagnosis.—Let us understand, first and finally, that but one diagnosis is absolutely and irrefutably dependable, viz.: the biologic diagnosis. Herein I would include not only the recovery of the pest bacillus from the patient, but the recovery and identification of the organism from inoculated animals, infected from blood, tissues, secretions or cultivated plague bacilli derived from the human patient or cadaver.
This entire process involves a lapse of time of several days, and, while it is indispensable in the earliest cases of an epidemic, and highly desirable for the proper study of all cases of plague, it is impracticable and unnecessary, in communities where plague is known to exist, to carry out more than the first steps of the biologic diagnosis, viz.: the recovery of B. pestis (morphologic identification) from the patient.
Necessity for Trained Bacteriologist.—It is evident that the services of a trained bacteriologist are indispensable in the accurate diagnosis of plague, unless (as rarely is the case) the observer himself is both clinician and bacteriologist. Even in this case it is far better for two persons, clinician and bacteriologist, to work together. I will not discuss the technic of the procedures of biologic diagnosis, which is described by Dr. Schöbl in the preceding pages. Except under circumstances of necessity, the clinician should always turn this work over to the bacteriologist.
Serum reactions, when present, occur too late to be of service in practical diagnosis.
The necessary procedures of the biologic diagnosis include blood-culture, smear examination (microscopic) of aspirated material from the œdematous tissues surrounding gland masses and from glands themselves; examination of sputum smears and of thick-blood smears.
All should be practised but, according to our Manila experiences, smear examinations of aspirated material and blood cultures are the most reliable methods, in the hands of a competent bacteriologist. Attention is invited to the reports of Dr. Otto Schöbl, already quoted.
Bacteriologic Procedure.—Dr. Schöbl was able to secure positive blood cultures, within 24 hours, from all of a long series of cases of plague, both bubonic and septicæmic. As much blood as it was possible to secure was aspirated from superficial veins and introduced into the culture media at the bedside, ten c.c. being secured whenever it was possible.
The smear preparations for staining and culture inoculations upon slants were also made at the bedside from aspirated matter obtained from œdematous periglandular tissues or from gland puncture, an aspirating syringe being used. The drop or two of fluid which can be expelled from the hollow needle is usually sufficient for smears and tube inoculations.