20
Paras. 15—16
But this hypothesis cannot for a moment be submitted to, unless we can
find sufficient evidence in fact and sufficient authority in literature to favour it.
In the meantime, I propose to employ it merely as a useful working
hypothesis for the better classification of observations.
I shall begin, then, with an exhibition of such facts as I could collect in
the brief period allotted to the work ; and shall then proceed to a theoretical
discussion of obscure points.
15. Mode of Investigation Adopted.—Had it been possible to examine
a number of cases of undoubted kala-azar from start to finish, the enquiry
would have presented less difficulty. As pointed out in paragraph 7, however,
medical men familiar with the disease are unwilling to give a definite diagnosis
of kala-azar in its earlier stages. It cannot well, then, be studied in its earlier
stages. There will always be the danger that any particular case of recent
fever may ultimately turn out not to be kala-azar at all. Now by the hypo-
thesis on which we are working, it is just in these early stages, and only in
them, that we may expect to find parasites and black pigment.
I had hoped to be able to overcome this difficulty by studying the disease
in a village recently and severely attacked ; but the same obstacle will present
itself here. In such a village we should certainly find many recent cases of
fever mingled with old cases of kala-azar ; but how be assured that the recent
cases are in the early stage of kala-azar at all, and not in that of the ordinary
malarial fever which abounds everywhere in Assam ? Nothing might be more
misleading than conclusions founded on such observations—unless the observ-
ations were protracted over a long period ; they would rightly be challenged
at once on the ground of this ambiguity.
Rogers has described this difficulty excellently in his report [page 25 et seq.].
The method adopted by him was to examine a number of cases of early fever
and then to return to them a. month or six weeksl ater, noting those which
had developed more marked symptoms of kala-azar in the meantime. For me,
however, this required more time than could be conveniently spared ; and was,
besides, open to the objection that the cases which ultimately proved to be kala-
azar may have contracted the true infection, on the top of an attack of ordinary
fever, in the interval.
On the whole, the course, which promised to be most instructive was the
simplest one. It was to sit down in a large village or town where cases of kala-
azar were occurring at the time, and to examine there all cases of fever of every
kind which could be procured, comparing the ensemble of the clinical and
pathological facts obtained. The town of Nowgong, where numbers of instances
both of recent fever and of established kala-azar were to be found in proximity
to the Civil Hospital, was admirably suited to the purpose. The Hospital was
popular and was attended daily by many out-patients ; the in-patients remained
willingly ; and autopsies were procurable.
16. Remarks as to the Cases Examined. — Every case of fever or kala-
azar examined by me, however briefly, will be entered in the following list.
My reason for doing this is to permit a judgment being formed on the evidence,
independently of any opinion of mine.
Many of the cases being out-patients were observed but once ; others were
refractory to examination ; others were so dull that I considered their evidence
as to their history not fit for record ; others again could be dealt with only very
hurriedly under pressure of the labour entailed by the necessary re-examinations
of other patients. Many cases which I should like to have considered were
abandoned altogether for want pf time ; so that the total number is not large,
while in many instances the notes are very short.
While engaged upon the work it was necessary for me to examine daily a
large number of mosquitoes in connection with my other duties in respect to
malaria, as explained in paragraph 1. This compelled me to confine myself to
the essential details of the cases, and to exclude reference to such secondary
symptoms as did not vitally concern the questions under consideration.
The points recorded were, the duration of the illness ; the history where
reliable ; the presence of the parasites and their varieties, and of the pigments ;
the temperature when it could be taken ; and the condition of the spleen and
liver.