The Portland daily press., 1899-08-25

Thus inoculated, the crow is consider ed
ht subject for another crop OF mosqui.
| toes, which may suck the Jualarial germs
from their victims blood and, after the
intermediate process, be ready to inocu
late other birds, as the investigation Il
carried on. One point has been settled
conclusively, so the doctors say. and that
is that the mosquito cannot directly In.
oculate malaria from an infected person
or bird to another. Although the mos.
quito may have malarial germs In its
stomach, 1t cannot transmit them until
the process of reproduction has been
gone through with, and the germs get
into the saliyary glands
Usually the birds are not Injured by
Tire incubation and survive to serve the
purposes of the doctors for further expert
mentations. The remaining mosquitoes
are killed off without compunction or
protest from NEUTRALITY-SUSPICIOUS.. Some
experimentsrs have had their birds sue
Dumb to the severity of the disease thus
introduced into their systems.
Investigation of the transmission of
malaria by mosquitoes was suggested by
the following facts as set forth by DIR.
William >. Thayer of Baltimore in q
paper on malaria rea before the Mary
land Public Health Association
Mosquitoes invariably exist In malar
GUS regions, and the maiarial fsyers are
more prevalent at those periods whsn the
mosquitoes are most abundant: they, ara
especially numerous In the regions about
swamps and marshes. where the dangers
OF Infection arc greatest. In a lnalarious
district there is greater danger of infec-
ton at about shutdown and at night, but
sunset and night are periods at which
, mosquitoes are highly active. The dan
gers OF Infection are greater near the
ground than In elevated positions. for
moquitoes are more numerous near the
of inf Xo.. L.
or on quiet nights than In windy weather
as wind Is particularly unfayorable TO
the mosquito.
Eniin Pasha was so convinced that the
bite OF the mosquito played an important
part In the etiology of malariaI fever in
Africa. that he always travelled with a
mosquito net, and escaped the disease.
bignami, further. has noted that in GER
tain parts OF Italy workmen who live in
ccnicai huts, with q hole at the top,
through which the smoke OF their little
IRE passes. are unusually free from the
disease, while those about thom may be
almost universally affected. OF COURSE,
the presence OF smoke Is one Of the sur
est projections against mosquitoes.
Koch, who last year devoted some
months in Africa to this study of malaria,
was strongly impressed with the proba-
bility OF this hypothesis. he says: THE
more l study this disease the more I in
oAinc loWaiu inc opinion that the latter
(transference OF the Infection by reason
OF the mosquito) Is the main, probably
the only method. Wherever one goes, be
finds tropical malaria and the mos1uito
present together. On the coast lin East
Africa) there are several places which are
free from the disease. One of these is the
island OF Chole which lies upon the
southern extremity of the island of Malta.
This IL the only place on the coast where
could sleep without q mosquito net. In
the mountains malaria stops at exactly
that point where no mosquitoes are to be
found. Inland malaria diminIshes to-
gether with the mosquitoes. At those
times Of the year when there are many
mosquitoes malaria Is moro severe
"1he natives Of Usambara Mountain
often acquire the disease when sthey de-
scend TO the iowlands. They believe 1t to
be due to the bites of the MOSQUITOES.
and call the disease by the same name
which they give to the mosquito-snbu. :"
Fortunately. 1t is believed that malaria |
Is the only disease transmitted BY live |
mosquitoes Filarla sanguinis hominis. |
Q hemorrhagic disease. is communicated |
by dead mosquitoes that impregnate |
water with the germs, which are fatal TO |
themselves. Apparently the mosquitoes !