The Pacific commercial advertiser. [volume] (Honolulu, Hawaiian Islands) 1885-1921, 1908-03-15

DR.. Currie Tells of the Bacillus
and What 1t Will
Not Do.

i
and purpose in the war for the exter-
mination of rats2'' said DR.. Currie, OF
the United States Marine Hospital
service. who is meteorological author
ity on the rat. "But it alone will
not exterminate the rat. 1t can be
made to serve purpose which nothing
else will, and it can be used where
other things can not be. But any hope
that by it disease can be introduced
among rats which they viii spread
among themselves to their own exter-
mination, is not at all warranted by ex-
perience.
| "Dr Danysz bacillus was used in
San Francisco for two years, from 1908
to 1905. For a long time I was the
only one in the service who had any
faith in it. But our experience there
| demonstrated that it was an efficient
agency in the fight against rats, and
in some degree our experience demon
/ strated its limitations.
1sone of the difficulties in its use
is its uncertainty. One tube of the
bacillus may prove very effective and
the next two or three be entirely in
noeuous There seems no way of
remedying this. DR.. Danysz himself
| says it is uncertain. Tt is probably
because of this uncertainty that such
contradictory ideas regarding it have
been entertained. Some experimenters
receiving an effective tube have con-
ceived an extravagant opinion of its
effectiveness, and others receiving in
effective ones, have adopted the opin-
ion that it is of no value.
"'The bacillus as an aid in the ex-
termination of rats is the result of
very ingenious adaptation or inversion
of the principle of the survival of the
fittest The bacillus itself is the bacil-
lus of a disease of mice which very
slightly affects rats-most rats not at
all. But DR.. Danysz by very in
genious process has increased its virus
power. His process is something like
this: He secures a large number of
healthy rats and having made a cul-
ture of the bacillus from the diseased
mouse he innoculates a certain number
of his healthy rats. The first of these
| that sickens is Immediately taken out
of that cage and put into another
tcage of healthy rats. The first of these
to sicken is taken out and put into
a second cage of healthy rats. The
process is continued for six times. In
each case, of course, it is the weakest
rat, the one most susceptible to the
disease, through which the bacillus is
propagated. By the time the sixth is
reached the bacillus has acquired a
virulence sufficient to make it deadly
disease to rats in general. A culture
of the bacillus from the last rat is
made and sealed in tubes, and this is
the commercial form in which it is
made and distributed. The contents
of these tubes must be used within
three weeks or they become innocuous.
That is why it would be difficult to
get it here for use. It is made by
the Pasteur Institute in Paris, and
now by the Pasteur Institute in Chi
eago. 1t was from Chicago that we
got it for use in San Francisco. But
it would be difficult to get it from
there within short enough time to
be available.
III. Hackfeld & Co. received guam
tity of what is called 'Ratin' from
Denmark a few days ago. This is the
commercial name of what I think is
the article being used in Denmark, of
which mention is made in the World s
Work, quoted in the Advertiser We'd
nesday. But it has been too long on
the way, and though I have used it
on some rats have here, it has not SO
far affected them in the least.
1.-THE method of using the Danysz
bacillus is this. Into a beef broth
culture the contents of one of the tubes |
is placed. The next morning the
bacilli have multiplied to the capacity
of the culture. AS much corn meal
is mixed with this culture as it viii
absorb and then this is placed where
the rats win get it. If it is eaten
by the rats within a few hours, it is
effective against them. If it is not
eaten within a few hours, it loses its
virulenee. a second culture from the
first, loses its virulence. That is one
of the peeuliarities of it. 1t has to
be renewed constantly from the virus
that has passed through the success
sion of rats.
'fIn San Francisco this Danysz ba-
cillus was used exclusively in the four
teen blocks comprising the Chinatown
of before the earthquake. We went
over those fourteen blocks once a week
for two years. We could go into a
Chinese house and ask to be allowed to
place it; they would object saying they
had children and they were afraid. In
such cases I would eat some of it right