The Prince George's enquirer and southern Maryland advertiser. (Upper Marlborough, Md.) 1882-1925, 1899-05-05

dramatically, will always cause a trans
terrence of the infection.

After all this, it is but rational to
conclude hat it is unlikely that intcc
ton occurs through the normal CASTRO
intestinal tract. This does not mean
that the parasites may not exist and
develop in Stagnant water. entering
the system i'll other ways. Indeed,
there is some reason to think that this
may possibly occur.
One of the oldest theories in connec-
ton with the disease has been that in
lection occurs through the inspired air.
and while no positive proof can be adj
vanced in its favor. it is hard for us to
completely abandon this theory. Many
| instances of malaria occur when almost
every other method of infection can be
ruled out. Yet as has been before
said, evidence proving that infection
| occurs through the lungs is wholly
| wanting. OF late years there has been
a strong tendency to return to an old
idea, namely, that the infection in ma
| laria may occur i'll many instances at
least. through the skin. the parasite
| being introduced hv th" bites OF some
| slctoria insect.
As matter of fact a sufficient num-
Der of individuals have subjected them
selves to the experiment to prove that
the disease may always he transferred
| from an inf, ctcd individual to healthy
| man Ivy intravcnous or hypodermatc
inoculation of blood. The same type
of fever and the same variety of para
sites always are reproduced in the indi-
| vidual who is inoculatcjl.
But especially interesting is the fact
that within few years several diseases
in the lower animals which depend upon
the presence of the parasite in the cir
culating blood have been shown to be
transmitted by the bites of insects.
Thus Professor Theohald Smith. of
Boston, at tha. time connected with
the Bureau Of Animal Industry in
Washington. showed that Texas fever
in cattle is due to the presence i'll the
blood corpuscles of 4 parasite closely
similar to that of malaria; and this
parasite is transferred by means of the
cattle tick. 4 disease of animals in
Africa known as Nagana Is due to the
presence in the blood of parasite
which is transmitted by the bite of the
Tsetse fly.
In man suspicion has fallen upon the
mosquito, and indeed, there is much
evidence which goes to suggest that
the mosquito may play a part in trans
| ferring the malarial infection. In the
| first place mosquitoes invariably exist
in malarious regions, and the malarial
fevers are more prevalent at those per-
iods when the mosquitoes are most
abundant; they are especially numer
Gus in the regions about swamps and
marshes where the dangers ofinfection
are greatest. In malarious district
there is greater danger Of infection at
about sundown and at night, but sun
set and night are periods at which
mosquitoes are highly active. The
dangers of infection are greater near
the ground than in elevated Positions:
but mosquitoes are more numerous
near the ground. The danger ofinfec-
tion is greater on quiet nights than in
windy weather; but wind is particular
ly unfavorable to the mosquito. Emin
Pasha was so convinced that the bite
Of the mosquito played an important
part in the aetiology OF malarial fever in
Africa that he always travelled with a
mosquito net, and escaped the disease.
Bignami further. has noted that in
certain parts of Italy workmen who
live in conical huts, with hole at the
top, through which the smoke OF their
fire passes, are unusually free from the
disease, while those about them may
be almost universally affected. o.
course the presence Of smoke is one Of
| the surrSt projections against mOSuui-
| toes.
Koch, who last year devoted some
months in Africa to the study Of maIa-
ria, was strongly impressed with the
probability of this hypothesis. He
says: The more | study this disease
the more | incline toward the opinion
| that the latter" (translerrence of the
| infection by means of the mosquto)
lis the main, probably the only meth
od." Wherever one goes he finds
| tropical malaria and the mosquito pres
| ent together. On the coast (in East
| Africa there are several places which
dTC llcc llolll tllt tlStiSt. 'lt Ol lllcSc
is the Island Chole, which lies upon
the southern extremity of the Island
=, of Malta. This is the only place on
the coast where | could sleep without
a mosquito net. In the mountains
malaria stops at exactly that point
where no more mosquitoes are to be
found. Inland malaria diminishcs to-
gethcr with the mosquitors. At those
times of the year when there are many
mosquitoes malaria is nor" severe.
! The natives OF Usambara mountain
often acquire the disease when they
! descend to the low lands. They believe
! it to be due to the bites of the mosqui-
: toes, and call the disease by the same
name which they give to the mosquito