The Savannah morning news., 1903-08-23
THE YELLOW FEVER GERM.
list, Tells of the Discoveries of tine
Investigating Commission.

OOmmhAAlOms
Below is given the first public state
ments of Mr.. j. c. Smith regarding the
discovery of the myxococcidium stego-
myiae, or yellow fever parasite, which
causes that disease. The announce
ment of the discovery was made sew
eral days ago in the report of the Vel
low Fever Commission, which has
been making Investigations in Vera
Cruz. The commission, in it's report,
acknowledged having received val
uaole assistance from Mr.. Smith, who
is a recognized authority on proto-
zoans, and whose work in connection
with the discovery of the parasite is
well known. At the request of the
Picayune the following statement was
given by Mr.. Smith:
Some years ago DR.. Sternberg, then
Surgeon General of the United States
army, promulgated his opinion that
yellow fever was due to a bacterium,
which he claimed to have isolated
from yellow fever patients. This bac-
terium he named bacillus X. After
repeated attempts to establish the con-
nection of his bacillus with yellow
fever this opinion was abandoned.
The next Investigator to come on the
field was DIR. Sanarelli, who claimed
that his bacillus icteroides was the
true cause of the fever. For some
years this theory was thought to be
the correct one, until experiments
were made which caused even its orig
inator to abandon it.
I'm 1880 DR.. Laveran established the
fact that malarial fever was caused
by protozoan parasite in the blood
Of the human subject. Fifteen or six
teen years after Drs. Ross, Grassi and
others demonstrated that the mosquito
was the dissemination of the maiarfal
parasite. Since then the mosquito has
been looked upon with suspicion in
connection with yellow fever, and 1t
was left to Drs. Reed, Carroll, Agra
monte, and Lazear to establish by
some very exhaustive and thoroughly
scientific experiments, that the mos
quito, stegomyia fasciata, communicat-
ed the disease from a patient to a nom
immune. This fact being established
1t was legitimate supposition, In view
of the analogy which was shown to
exist between the transmission of NIL
larial and yellow fevers. that the cause
of yellow fever would be shown to be
an animal parasite. Investigators in
this line were ever on the alert for this
parasite, and certainly some of them
have had glimpses of 1t, but 1t fell
to the lot of the Yellow Fever Com
mission of 1902, appointed by Surgeon
General Wyman of the United States
Marine Hospital Service, and consist
ing of Drs. Parker and Pothier and
Prof. Boyer to establish in connection
with myself, the fact that the true
cause of this dreaded disease is a verit-
able animal parasite. The report of
this commission has been published re-
Gently, and as it has been written for
the scientific world it abounds in
many necessary technicalities, which
are not ineligible to the general read
ar ~ a nCnaRintlV
in this city, is deeply interested in
this matter, 1 will, in virtue of having
been connected with some OF these in
designations, attempt to put in pain
language the principal facts relating
to this parasite, which has been named
myxococcidium stegomviae.
VERY many adult insects are infect
ed with protozoan parasites, and this
fact made it absolutely necessary for
the commission to raise from the
larvae the mosquitoes used in their ex-
periments. These larvae were gather
ed and placed in aquaria so guarded
with mosquito netting that when they
developed into the adult form they
were confined in the aquaria- A few
days after leaving the pupai stage
these mosquitoes were taken from their
confinement and given their first meal
| by allowing them to suck the blood of
| a positively determined case of yell
| low fever from four to six days old.
| These mosquitoes were again confined
| and some were killed three days after
infection, and others on each successive
day until more than fifteen days after
infection. The mosquitoes Immediately
after being killed were passed through
a laboratory process unnecessary to
mention here, whereby they were hard
ened, cut in long sections of about
one-sixteen hundredths of an inch in
thickness, stained with various dyes,
and then mounted on thin pieces of
glass. They were then ready for ex-
animation with good compound mi
croscope magnifying the sections one
thousand times.
ut was after these infected mos
quitos were mounted on the glass slips
that my services were called into re-
QUESTION, and the following descrip-
ton of the parasite will be as / saw
and interpreted it.
1.-THE main facts are identical with
those of the report, but I will give a
more detailed account of the various
phases.
"It is very essential that the investi-
gator be thoroughly familiar with the
internal anatomy of the MOSQUITO and
well acquainted with that large and
| puzzling class of microscopic animals
the protocol.
Description of the various phases
| of the parasite as seen in the mos
| quitos after being killed from three to
| fifteen days subsequent to infection.
| In the stomach (midgut) of mos
| quitos killed three days after infection
many partially digested blood corpus
| cles were found, and distributed in this
| mass were number of exceedingly
small elongated bodies, each pointed at
| one or both ends and each with q, CEN
trail nucleus. These bodies, on ac-
count of their small size, Transparent
cy, and failure to take the stain used.
| required very critical manipulation of
! the light and focus of the object glass
to demonstrate their presence. These
were the parasites taken from the
yellow fever patients with the first
| meal of the mosquitoes. The atom-
achs of the mosquitoes killed four days
after infection were free from good
(blood) and contained the same bodies.
but increased much in size, their meas
urements being about one-seven thou
sandths of an inch.
Many were in small clusters, while
others were distributed about, singly
and in pairs. Each one of these bodies
had a single central nucleus and a per-
manent vacuole in its interior half.
Il believe tina this vacole will prove
characteristic of this parasite.) The
general shape Of the parasite was
ovate, the posterior end somewhat
rounded, and the anterior end pointed.
Among the distributed forms the fol-
lowing peculiarities were noted: (a)
Two normal-shaped forms were united