Evening bulletin. [volume] (Honolulu [Oahu, Hawaii]) 1895-1912, 1909-01-18
DR.. Brinkerhof..'s Report
On determination Of
That Pest
CANNOT COMPLETELY DESTROY
But MUCH Can Be DONE
Constant Watchfulness-Traps, Cats.
Notify Authorities When Rats
Become Numerous

lntrOductlOn.-The question OF de-
stroying the rat Is an important one
In all communities, particularly
where plague has been or may again
be epidemic or endemic. This ques-
ton is not only Of Importance to the
public officials charged with the care
of the public health, but also is OF
great Importance to the whole COM
munity In an economic way. Lantz
Farmers Bulletin, No. 297, U. s. De-
partment Of Agriculture) states that
the rat is responsible for the destruc-
ton of many millions of dellars'
worth OF property annually in the
United States. He considers the rat
to be the cause Of more money loss
than all other mammals together.
In this community, besides this lit
tie recognized economic reason for a
war against the rat, the question OF
the role OF the animal In the dissem-
nation OF bubonlc plague is of the
first importance. II is an established
fact that the rat is the carrier. in the
vast majority Of cases, OF the disease
from one community to another and.
working in conjunction with the rat
flea, Is the means OF perpetuating the
disease in a given community.
Owing to the cosmopolitan distrl-
button OF the rat 1t is OF little use to
try to exterminate II in any given
locality, II such thing were possible,
unless the re-introduction OF the spe-
cies were prevented. This being the
case the futility of attempting to rid
community of rats when the next
ship may introduce dozen or more
individuals is obvious. Even II CON-
plete determination OF the species Ia
not aimed at II IS important that the
use of rat guards on all lines from
foreign ships and other quarantine
precautions be insisted on. not alone
to prevent the ingress OF normal rats
to add to the breeders, but, far more
important, to prevent the entrance
into the community OF rats which
may be infected with plague. Sup
posing that this exclusion OF rats
could be arranged for land on an
island such thing is possible IL any
where), what chance Is there OF the
complete determination OF the rat
and how should this end be sought ?
Before beginning this discussion II
Is well to bear in mind few biolog-
ical facts about the rat. particularly
its reproductive powers These ami
mails have six to twelve at a litter
and three to four such filters are
born each year. The females begin
TO breed at from three to four months
of age. A simple calculation will
show that the rate of multiplication
of the species is so fast that only the
most energetic and wholesale meth.
DDS OF destruction will have any ef.
feet upon their numbers. = r"f F.
II seems almost hopeless to expect
that an animal OF such tremendous
reproductive power could be total,
exterminated unless the cupidity OF
man could be called into play. II
rat-skins were as valuable as thos,
of the silver fox the rat would soor
be exterminated or confined to arti
ficially controlled BREEDING places. II
seems well, therefore, to face the fac
fact that total extermina ton is no
within the bounds OF possibility. Elk
ception will at once be taken to thi
statement by some on account OF tn,
widespread belief that an Infection
disease lie. g., Danish or other virus,
can be expected to utterly extermi
nate a species. This belief is not II
accord with what we know of In
fectious disease. All infectious dis
eases are examples OF parasitism
That is to say the disease is the by
product OF the attempt OF minut
and low form OF animal or vegetabl
life to gain a living by becoming
parasite upon higher form of life
II is not to be expected that this re
lationship, when detrimental to tn
higher form. will be established witt
out some attempt on the part of tn
living being attacked to resist tn
invasion OF the parasite. Our mod
ern knowledge of the treatment an
control OF infectious disease rests IN
on an understanding of this mechan
ism OF resistance of the attacked be