64
Paras. 36 & 37
(see especially those from Dr. Jackson that the disease was communicable and
that it attacked members of the patient's family. It is impossible to read these
excellent passages of Rogers' work without feeling convinced that the Rungpore
and Burdwan fevers were identical in symptoms and epidemiology with kala-
azar, kala-dukh, and kala-jwar, and that all alike were, or are, epidemic and
communicable diseases.
But the point of all this argument may be turned, and in the case of
Rogers' forcible parallel has been turned, by the criticism that all these
so-called epidemics of malarial fever were in reality epidemics of other diseases,
typhoid in Europe, ankylostomiasis in India.
In my opinion this criticism is quite unjustifiable. In the ease of the
epidemics in Europe and America, it ignores the fact that even before the
differentiation of typhoid and ever since the days of Torti, the profession was
quite able to distinguish between malarial and continued fevers. In the case
of the epidemics of India and Mauritius it ignores the fact that the existence
of the typical malarial fever and of enlargement of the organs was expressly
noted. In short, it asks us to assume that the scores of medical men who had
to do with these epidemics were most grossly ignorant of their profession, while
it invites us to prefer to the opinion of these eye-witnesses the diagnosis of
critics who certainly never saw the epidemics and who have probably never
even studied the records of them. It is quite inadmissible, for instance, to
declare that the Mauritius outbreak was really ankylostomiasis. I have studied
some of the records of that outbreak. It was not ankylostomiasis, nor
anything like it.
A much more reasonable criticism would be that these epidemics were not
due to paludism, but to a disease symptomatologically similar to kala-azar to itself.
It may be said that all those epidemics in various parts of the world were really
instances of kala-azar which has long been spreading in various quarters,
though always mistaken for malarial fever. But this begs the question - still
to be finally considered—whether the diseases are identical or not.
Theories attributing the enlargement of the organs to a substratum of
" general malarial taint " and the spread of the disease to some other cause, are
always insupportable. I have studied in some of the most malarious spots in
India, and, even in them, never saw any general enlargement of the organs
approaching in degree that almost always found in kala-azar. As remarked
in paragraph 5, any general malarial taint producing the state of things found
in this disease would suffice in itself not only to decimate, but probably to
exterminate, the population. No ; we are obliged finally to admit that in all
these epidemics referred to the epidemic disease is itself a single entity—a fever
involving enlargement of the organs ; and that in the later epidemics studied
by Rogers this fever is also communicable from the sick to the healthy.
37. Is Malarial Fever Communicable ? — But malaria is an emanation
from the soil, it is a product of decomposing vegetation, it springs from water-
logged areas, it rises in mists and exhalations, it is not communicable by sick
persons.
This is the great difficulty felt in regard to these outbreaks by everyone
since the days of Dr. Jackson.
The difficulty is met by this question—What sufficient reason have we
for assuming that malarial fever in general is not a communicable disease ?
I seek in vain for a reply—there is no sufficient reason.
What, precisely, do we know regarding the exact mode of infection of
human malaria ?—absolutely nothing.
The mode of infection of malaria—we find ourselves at a step in the
midst of the malaria problem. I propose to deal very shortly with it here,
because, as noted in paragraph 7, the study of the question concerns other duties
of mine, apart from those extending to kala-azar. But I may endeavour to
define our ideas on the point.
What do we know about the gross epidemiology of malaria ? -- very little.
Its incidence varies according to locality and season; it seems to be connect-
ed in some way with dampness. That is about all. Similar facts are known
about many diseases.
What about the exact mode of infection ?—Only endless hypotheses-
conduction by the air and the lungs, by water and the alimentary canal.