The Washington herald., 1909-02-21
MOSQUITO IS DEADLY
Sir Patrick Manson Tells Of
His Discoveries.
INSECTS DIFFUsE DISEASES
Famous Scientist Tells of Methods
Whereby Proof Was Found that
Malaria. Yellow Fever, and other
Diseases Are Inflicted on Human BE-
inEs by BIOod-sucking Mosquitoes.

LAlaA News 8lLHAl-
London. Feb. &-Sc.ence never had
better exponent for the layman than Sir
Patrick Manson. the man 10 whom, above
all others. is due the credit Of discover
ing the secret OF the spread Of many dis
eases through the medium OF mosquitoes
and other insects. In a luminous speech
at a gathering in his honor. the other
day, he told the wonderful story Of mis-
investigations IN language simple enough
for the man IN the street to understand.
Sir Patrick's subject was My personal
experiences Of the mosquito" and he
said. in part:
The success Of the mosquito theory.
both as regards filaria and malaria.
meant that the idea OF insect transmits
sion was not 20 stop at these two dis
eases. A good many years ago it oc-
CURED to Findlay. Of Havana. that the
mosquito OF that country might be the
agent for the spread Of yellow fever,
just as I had shown II to be the means
by which flaria is spread. He made
several experiments. some Of which
seemed 10 countenance the idea But the
subject was not then proceeded with.
Some years ago an American commits
sion, which had been sent out TO study
yellow fever. took the matter up again
and has shown that a certain kind OF
mosquito. II il feeds on a yellow fever
patient during the first three days Of the
disease. contracts thu virus OF yellow
fever; that II this insect. so infected. Is
kept for some ten OF twelve days, being
carefully fed the while. and is then al
lowed TO bite some one who has never
had yellow fever. il viii confer yellow
fever on the individual so bitten. That
discovery has rid Havana Of yellow fever.
and that discovery IS enabling the Ameri-
cans to construct the Panama Canal
Remedies OF the Future.
The success Of these investigations in
the case Of the mosquito has stimulated
further work on other blo0d-sucKing IN
sects. and now we know OF a good many
other diseases which are so transferred.
We know that a certain tick conveys an
important disease Of cattIe-Texas fever
which prevails in many parts OF the
world. making serious fnroads on pastoral
industry. We know that a similar disease
IN dogs Is conveyed BY ticks.
LAlEAE = E-UOA ALAAl AlAE A1EAzE ~ aGLS
in a Ike manner as regards the ny dis
eases OF cattle and the fly disease-the
sleeping sickness-of man We know that
q certain kind Of tick is the medium by
which a most serious kind Of African
fever-relapsing fever-is conveyed we
are fairly sure that other diseases are
conveyed by bugs and lice and so on.
Almost every month a fresh discovery
Of rnfu Tnu0-7u~F0r IN hnfur v7oNa
doubtless the result will be practical
measures which viii tend 20 minimize the
dangers OF these diseases. II not actually
succeed in preventing them. Hundreds
OF workers are now busying themselves
with these problems.
Those Of Us who have seen the progress
OF events OF late years IN Africa nave
been struck with the remarkable way in
which diseases which had hitherto been
confined TO very limited areas are gradu-
ally extending over q greater part OF the
continent. This undoubtedly is the result
OF the moving OF the population. OF in
creased facilities OF travel, and go forth
the opening Up Of the Dark Continent.
Disease May Spread.
What is happening in Africa VIII hap
pen elsewhere. Increased facility for
rapid travel implies the spread OF disease.
There are several tropical diseases, no
tally malaria and yellow fever-botn mos
quito-borne diseases-whIch are still geo
graphically linited-that is to say, there
are places where they do not occur FOR
instance, there is no yellow fever In Asia
OF East Africa As regards malaria. It
does not exist IN many Of the Pacific ISL
ands Fiji. for one, is Tree-
My belief is that II precautions are
not taken in time. both OF these diseases.
yellow fever and malaria, will extend
their range: that with the opening I'D Of
the Panama Canal and BY the repeated
passage Of rapid steamers across the Pa
cifc yellow fever viii be introduced in
the Sandwich Islands. Manila, and to the
continent OF Asia. Ny belief also : that
Il measures are not taken to prevent the
introduction OF fever-carrying mosquitoes
into some countries hitherto free from
malaria, by and by these countries will
become. instead Of healthy. exceedingly
unhealthy and nslarious: that the ex-
perience OF the Mauritius viii be repeated
elsewhere
You know. in the time Of Paul and
Virginia. the Mauritius was a veritable
heaven upon earth At the present time
as regards health. this island is GER
tainly quite the reverse. In an evil day
the malaria mosquito was carried 10 the
Mauritius, and nov the island is fun Of
them, and correspondingly unhealthy
What guarantee have we that in islands
under Ike climatic eonditions-e. 2. Fiji
and the Sandwich Islands-a similar ca
lamity may not Occur2
This is the moral I would like 10 i'm
press upon you. Discovery Is Of little use
unless it has practical application. The
practical application Of the discovery that
these various insects are the distributors
CT conveyors Of disease germs is the I'M
mediate enforcement OF measures which
wiz tend to repress these germs"
ET0N RULE IS UNPOPULAR.