The times., 1899-06-27
DANGER IN MOSQUITOES.
A Theory That They Disseminate
Disease and Pesfifepcc.


summer resort. but IL the medical men are
right freedom from mosquitoes will here
after be the most important consideration.
These insects are to be regarded hereafter.
not only as an annoyance but as breeders
OF disease. especially Of malarial fever.
II is true that this disease Is net so preva-
lent in this country as in some part OF
Italy and Spain. where oae-half of the
population is affected By 1t. nor so deadly
as In India, where. according to Surgeon
Majo. Ross, the British Governments ex-
pert. about 5,000.0G0 people are killed by
II every year; yet unwary tourists are
more or less exposed to II In all countries.
and II Is not pleasant to think OF going to
the country in quest of health and bringing
back instead a system infected with ague-
The question whether mosquitoes are really
responsible for malarial fever Is, there
fore. of Importance TO the public at large
as wen as to physicians.
As the name indicates, malaria used
to be considered a disease caused by bad
affair poisoned by some unknown sub
stance suspended in IT, There were how
ever. so many facts not accounted for
on this hypothesis that il fell into disre-
rute among men OF science. and its place
was taken by the theory that the germ
of this disease is taken into the system in
contaminated drinking water like The
cholera, concerning which there is now
no, doubt tnat they are spread in this way
An Italian hygienist went 50 far as to pro-
pose that the name malaria. TO avoid con-
fusion. should be changed to malagua. The
water -conduction theory is still held hy
scme authorities; and even the champions
Of the mosquito theory, like Koch, coun-
sci the boiling OF suspected water. An
other advocate of the mosquito theory.
DR.. Bignamf. was led to doubt the water
theory by the fact that in the Roman
Campagna there are many malarious places
where water of the same excellent quality
Is drunk as in perfectly healthy places in
the immediate neighborhood But why
should not water be the medium in some
cases, and mosquitoes in others? If we ex-
clude water Tor ice containing the germs
which are not injured by eold}-it is inpos-
sibie TO account for the occurrence OF ma
larial epidemics in Russia and elsewhere in
zero weather which is fatal to mosquitoes
reconciliation between the water and
mosquito theories may be found in Dr.
Manso's suggestion that malaria infected
mosquitoes may die in pools and contain
mate the water drunk by man. while in
other cases the disease is inocuIated by
the insects.
Although the notion that mosquitoes are
the agents of spreading malarial tevers
has been prominently before the public
few months. since DR.. Koch lent it the
weight of his authority, il is by no means
novel suggestion in medical literature.
As far back as 1901 DR.. John Crawford
had an article in the Baltimore Oh
server" on The MOsquital Origin OF Ma
laria." 1t is indeed strange that general
attention should not have been given to
this matter long ago. since there is such a
close association between mosquitoes and
malarial fever. Mosquitoes are usually
associated with swamps, and malaria was
long known under the name Of marsh mi
asm or paludal poison. II has long been
known that even in the most malariOus
regions of the tropics the use of gauze
wells by day and mosquito nets at night
prevents malaria-a circumstance sub
versive Of the air theory and directly po.nt-
ing to the agency Of mosquitoes. It was
necessary, however. that the modern germ
theory of disease should have been sug
gested and widely accepted before the
agency of mosquitoes as a medium of con-
/ VeyIng disease could be comprehended.
After this was done progress was rapid.
In 1897 Major Ronald Ross was sent to
India to study the disease which there
kills more Of the British army than are
killed by the enemy. and which checks the
progress OF civilization in some OF the
richest regions in the world 1898 the
a.
TO East Africa On similar mission He
| returned declaring that malaria is the
most terrible agency man has to- contend
| with in those regions. and that the full
| advantages OF colonies cannot be realized
until It is overcome. He found how
ever. that quinine, given at the proper
time Ito be determined by microscopic
analysis Of the blood. is an almost infalli-
Bile cure.
| In the mean time. an important step
| toward proving the mosquito theory was
made in Italy. More than hundred
species OF mosquitoes are known in va
| rious parts of the world. and il is be-
lieved that different species inoculate diff
! ferent varieties OF maIarial fever DR..
/ Bignami captured a number of the species
| known as anopheles cIaviger. in the
malarious region about Maccarese. and by
allowing them TO bite a healthy young
man in Rome who had never had malarious
trouble, succeeded in giving him the fever
of the tertian type, which is prevalent at
! Maccarese. DR.. Koch on his part brought
back from Africa a number Of corrobor-
! atiye facts. He found that there was no
malaria on the hills. where mosquitoes.
| too, were absent: that in the interior ma
laria diminishss together with mosquitoes
and that at the seasons of the year when
mosquitoes are most abundant malaria is
I
ChoIe. which is free from malaria and
was formerly used by the Arabs as a
| health resort. and found it the only place
where he could sleep without n mosquito
| net.
| Mosquitoes are now accused of convey
| ing not only malaria. but leprosy. yellow
fever. and other contagious diseases.
though it is certain that they must share
the burden with flies and other insects that
4 INF, rfT hos
not been disinfeeted, and afterwari con-
taminate the food. The experiences in our
army camps last summer proved that suffi-
| GENTLY. The important lesson to be
drawn from this-constituting a great ad-
| vance in medical science-iS that visible
| insects are as dangerous foes to our health
| as the mueh-discussed microscopic baciili.
| Flies can be easily made harmless by sim
| ply disinfecting the sewage where it re-
mains exposed to the air. Mosquitoes are
| less easily dealt with. Drainage and cul-
| tivation of swampy soil help TO diminish
| their numbers and petroleum or psrman-
ganate of potassium have been found useful
| in killing the larvae in the water But
mosuuito-nets and wells in dangerous local
tiles are the only things to be relied on
implicitly. Perhaps the most important
| result of all these Investigations is the
lesson that what is dangerous in malarious
regions is not the night air. but the roe
| turnal mosquitoes. Windows may. there
fore. be left open safely. provided there is
| a screen or a nosquito-net. and the popu-
| lar delusion that night air is in itself dan
| gerous has received its death-blow after
| having shortened the lives of millions OF
people.
The Transvnni Troubles
(From the indianapolis Ncws-)
Ii there iS TO be war in the TransFaui. II.
| first aggressive move will have to come frou
| Great britain and the situation viii have %