14
Para, 11
They were all frequently observed by me in Assam. In Gauhati, in the
excreta of 5 hospital patients examined, I observed the eggs of round-worms in
2, of whip worms in none, of ankylostomes in 4, amoebae in 3, and cercomonads
in 1. In Nowgong, in the excreta of 17 patients examined, round-worms were
present in 8, whip-worms in 11, ankylostomes in 11 ; amœbae and cercomonads
were not carefully searched for. In addition to these aniphistornum hominis
occurred in two out of eight autopsies. These results agree with those of other
observers (except in regard to the protozoal parasites, which have been much
overlooked in India) ; and there is no doubt that the entozoa referred to are
very common in Assam. The parasites of the red corpuscle were found by me
in 30 out of 73 people searched for them, mostly cases of fever, in Nowgong.
In considering the question whether any of these parasites cause any parti-
cular disease, it is necessary to show not only that the parasite is present at one
time or another in the course of the disease, but also that it can and does
produce the symptoms—the disease must be looked at as a whole and we must
ask ourselves whether, judging from our previous knowledge of the parasite, the
symptoms are likely to the produced by it.
We may, for example, rest assured that none of these organisms can cause
small-pox, or cancer, or influenza. On the other hand, it is often prima facie
possible that a case of anæmia may be due to ankylostomes, and of fever to the
parasites of the red corpuscle.
Applying this test to the two diseases described and differentiated in para-
graphs 6, 7, 8, and 9, it will be obvious at once that the "anæmia with dropsy"
may be due to ankylostomes and the "fever with enlargement of the spleen
and liver," to the parasites of the corpuscles. At the same time it will be
equally apparent that the fever in question cannot be produced by the ankylos-
tomes, nor the anæmia (without fever) by the blood parasites.
As a matter of fact, with regard to the anæmia, it is already established
by the labours of Ruddock, Giles, Campbell, and others (in Assam alone) that it
is produced, at least in the majority of cases, by the ankylostomum duodenale
—that the anæmia with dropsy which I have so frequently referred to is, in
fact, ankylostomiasis.
Similarly, we may rest equally assured that the fever with enlargement of the
spleen and liver, called kala-azar, is not ankylostomiasis. So evident is this fact
that I think we may safely accept the opinion of Sir W. R. Kinsey [ 11 ], him-
self a great authority on ankylostomiasis, to the effect that no elaborate discus-
sion of the matter is required. The symptoms of ankylostomiasis, pure and
simple, frequently studied in Europe, Egypt, Ceylon, America and elsewhere, are
quite different and remote from those of kala-àzar pure and simple. If kala-azar
has ever been thought to be ankylostomiasis the error has been probably due,
as I have suggested in paragraph 8, to a confusion as to the identity of the
disease at the beginning of the epidemic. If kala-azar be defined as an acute
fever, especially a fever with enlargement of the spleen and liver, it cannot be
ankylostomiasis. The deduction springs at once from the definition.
Rogers, not contenting himself with a simple discrimination of this nature
(which, I confess, appears sufficient to me), has gone further and has argued the
matter at great length. In [ 12, p. 249 ] he gives an excellent summary of the
differences between kala-azar and ankylostomiasis ; while in his report [ 4 ] he
examines some of the differences between the anæmia of the one and of the
other disease. It is perhaps to be wished that he had increased our indebted-
ness to him by actually giving the blood-counts in sufiiciently long series of cases
accompanied by counts of the ova of the worms found in the excreta. The short
time at my disposal rendered it inadvisable for me to attempt any confirmation
of his work in this respect ; but I think that, all things considered, it is impos-
sible to avoid at' any rate the conclusion arrived at by him.
The fact is that ankylostomes can no more be the cause of kala-azar than
the other worms just referred to can. The effect of all of them on the economy is
perfectly well defined. We know that in sufficient numbers some or all of
them may produce such symptoms as emaciation, dyspepsia, diarrhoea, even
slight fever, anæmia, eclampsia, icterus, ulcération of the bowel, and so on.
Lately, moreover, observations have been recorded tending to show that worms
secrete a toxic material which may influence the system in many ways
Manson in the discussion on kala-azar before the Royal Medical and Chirurgical