Evening star., 1925-08-27
BACKGROUND OF EVENTS
BY PAUL y. COLLINS.

When these breeding places are about
Summer resorts which do not oper
up until July the new mosquitoes ar
rive before the resorter does. The
time TO destroy them Is in the Spring.
while the snow is melting A few
drops OF kerosene sprayed over the
little pools of water will rid the local.
ity for all the Summer
Any mosquito may travel long dis
tances when carried in AUTOMOBILES
or trains, or blown by strong winds
X x X
1t is popularity supposed that much
rain insures abundance of MOSQUITOES
but the contrary is true For ex.
ample, Washington has had abun
dance of rain this Summer, but com
paratively few mosquitoes. This is
because the rain washes down the
sewers and the roof cutters and pre-
vents water standing long enough to
hatch the eggs laid therein.
In Louisiana a marsh has been
sprayed from an airplane with arse
nate of lime, mixed with the dust OF
the road. In the test there were first
placed basins of water into which
larvae were put. These ba sins were
located In various parts of the marsh
and the spraying was found to have
| killed all the larvae in all the basins
Enthusiastic laymen, basing thei1
conclusions upon that test, have pro
posed that President Coolidge insti
tute movement nationwide for
spraying from airplanes or airships
the entire continental United States
so as to rid the continent of all mos
quitoes. SCIENTISTS say that such a
campaign would be needless and flu.
10, ;,l
yellow fever and dengue MOSQUITO
travel any distance from their breed.
ing grounds; so the humiliation of
the others is matter of local atten
ton.
Ihe anopheleS mosquito. which con
veys malaria, breeds only in clean wa
ter, preferably with grass growing ir
II. A bite from an anopheies results
In injecting into mans blood a para
site which causes malaria. Quotine
from pamphlet by DIR. H. r. Carter
senior surgeon of the United States
Public Health Service:
The parasites which she injects en-,
ter the red blood cells. They are then
extremely small. They grow by feed
ing on the blood cells and get bigger
and bigger. Then their edges become
scalloped and they divide into a mum
Der of wedge-shaped pieces, meeting
In the middle like a piece of pie. The
blood cells break up and set the young
parasites free, and each one of them
starts OF as new parasite on it's own
account and tries to enter another red
blood cell and repeat the process of
its mother parasite. There are three
kinds of parasites, causing different
kinds of malarial fever. 1t is
estimated that at least $50, 100000 OF
parasites must divide at the same time
to liberate enough poison to produce a
chlll-generally many times more than
this
The scientist describes the further
process of spreading the malarial fe.
YER as follows: The man who has the
fever is bitten by another mosquito
which sucks from his blood many OF
the malarial parasites. These pass into
the stomach of the biting mosquito
and if both sexes are thus taken to-
gether into the stomach of the mos.
quito they there breed millions more
parasites, which in due time rise to
the saliva of their host, the mosquito.
If, then, that poisoned saliva enters a
human victim by his being bitten by
the mosquito, new case of malarial
fever results-another source of para
sites sto feast upon red corpuscles and
weaken the victim while adding mil
lions more parasites. In the same
.FN