New-York tribune., 1897-08-22
MOSQUITOES AND MALARIA.
ARE THE FORMER THE CHIEF VEHICLES
OF THE LATTER?


country during the last few weeks calls atten-
ton to a theory which has been widely dlscuSScu
l,y medical experts abroad for more than year
7, MAY. be said certainly with a show of truth
fulness. that this destroyer of human happiness
has enough sins to answer for already "lthout
Tho addition of any further counts to the lndict-
mont especiallv if these latter cannot be 1uily |
established That however, is question Oh
ethics which need not be discussed IN TINS coh-
ncction The mosquito will be given a chance
to state her side Of the case before Juos"ie"' %
rendered 1t is her side, because the ha'ui"
lists declare that only female mosquitoes uo INV
biting How the male mosquito gets MS hV'ns
we are not told 49,
Not long after Iaveran discovered (as he dlo
about seventeen years ago. that there Is d p"'"
si, necnIiar to malarial diseases, he found that
This microscopic creature existed not only IN the
blood Of fever and ague patients but also i'll 'he
s;omachs of mosquitoes. Up to date TINS par
ticular form of life has not been found III any
other animal or insect. Laveran was thus leu
70 suspect that the mosquito was an agent IN '"e
dissemination of malarial poison. For more
than a decade however. the medical profession
was disnclinod to accept the parasitic theory OF
malaria In the mean time naturally, the mos
ouito was ignored But within the last two
,eore euch convincing evidence has been pre-
eentcd bv Independent investigators that the
first mart Of LaVeran's announcement is gen
orally considered altogether correct. 1t is now
in order therefore, to consider the other part OF
it, How far. if at all. is the mosquito RESPONSE
BILE for the distribution Of maarial parasites
among human subjects?
II the question were put in the opposite fash
ION # might be answered easily. The mosquito
thrusts her bill down far enough into mans
hand TO suck blood She drinks her fill, If she
IS not interrupted OF whatever microbes, para
sites or inanimate poison that fluid contains she
is sure to take sample If she gets more 'hah
she likes or if she has an attack OF chiiis ana
favor week or two later in consequence, of
course that is her own lookout she does ho'
nav. Cor what she takes. and cannot justly blame
her victim The mosquito is credited with let
ting severely alone people who indulge freely in
alcoholic beverages In the interest OF puhhc
morality. perhaps. that fact ought to be con
caaled Nevertheless it reveals the possession
Of certain powers of discernfnent Anu II d
r,osouito knows enough not to touch an "old
soak if is a fair presumption that she has in
telligence enough to abstain from blood imbued
with malarial poison if 1t disagrees with her
liver
But that is not the point. The real problem
,s how do the parasites get back again into
human blood. This matter was discussed at
considerable length In an address gwen last
wear by Or. Patrick Manson, physician to the
Seaman's Hospital in London and lecturer in
two other hospitals in that city. DR.. Manson
saws that few days after gorging herse1 Win
blood the mosquito lays her eggs In the water
and then dies. The parasites that are left IN her
body eventually become free and then may be
drunk with the water If the pond where the
MOSQUITO dies should dry up, and the parasites
are left in the sediment they may be blown
about with the dust. and thus he breathed into
tho human system In corroboratiOn of one
part of this theory DR. Donald Ross, OF India,
ground up some "malariazed mosquitoes" in
water gave a small quantity of the latter to
healthy native who eleven days later. developed
fever and aguc.
II might be objected that, while this is a natu-
raj and possible way OF communicating disease
TO a human subject. it is not the only one. and,
in fact il might seem to be the least probable
of a number of ways. DR.. Manson, in antic
patton Of that argument, goes into the life his
tory and nature of the parasite very fully For
different malarial diseases there are different
.pecjes of the parasite. Some readily
detected than others But they all behave in
shout the same manner. H. at the very begin
ming of a rnalarial attack. especially during
chill. the blood be examined 1t will be found
that there are minute clumps of cells, like a
microscopic mulberry bunch of grapes. each
with q dark spot in il. They inclosed in a
,hin shell Of hHmOglObin. Later in the course
of the disease some Of these escape from the
eheu and are floating around separately. Each
clobuIe though is a distcnded red cOrpuscle
sn which there are one more parasites The
,ntter undergo some change of form, but rarely