The leader., 1905-08-12

on one SIDE Onfy. A brave nOn-1mmun9
entered and remained long enough to
allow himself to be bitten several
times. He was attacked by yellow fe-
yer, while two susceptible men in the
other compartment did not acquire the
disease, although sleeping there thir-
teen nights. This demonstrates in
the simplest and most certain man
ner that the infectiousness of the
building was due only to the presence
Of the insects.
Every attempt was made to infect
| individuals by means of bedding,
| clothes and other articles that had
been used and soiled by patients suf-
fering with virulent yellow fever.
A Convincing Report.
Naturally yellow fever is transmit
ted by the mosquito. The harmless
ness of fomites has been fully demon.
tsrated by our experiments in 1900
and 1901, in which three young Ameri-
t cans sept for twenty consecutive
nights in a room from which mosqui-
toes were excluded garnished with ar
ticles soiled with discharges from fa-
tai and other cases of yellow fever.
Three and four large boxes were
packed and unpacked each morning
by these nonimmunes, who suffered
no disturbance of health from these
exposures. The room was twenty
feet by fourteen feet, double walled,
tightly sealed, heated to above 80 de-
grees Fahrenheit and dark.
1.-TWO other nonimmunes then occu-
pied the room for twenty nights, while
additional articles of bedding and
clothing were added. They slept in
the garments and between the sheets
that had covered cases of yellow fe-
yer, some of which were fatal. The
result of the second attempt was nil.
A third attempt was then made with
two additional nonimmunes, equally
without success. Not the slightest in
disposition followed close and inti-
mate contact with this repulsive mate
rial in any case. Temperatures and
pulse rates were recorded at regular
and frequent intervals. Four of these
seven nonimmunes were subsequently
| infected by blood injections and by
means of infected mosquitoes.
Another kind of experiment was
! Included in the Cuban investigations
of yellow fever. A room was pre-
| pared so as to preclude the possibility
of infection by fonites (infected arti
cles). Every article contained in the
room had been previously disinfected
and was thoroughly clean. The only
/ possible means of infection with vel
low fever was by infected mosquitoes,
| liberated in the room containing the
| human subjects of the experiment.
! Yellow fever promptly followed the
| introduction of mosquitoes into the
room.
What Experiments Proved.
Besides the experimental cases
caused by mosquito bites. four non.
immunes were infected by injecting
blood drawn directly from the veins
of yellow fever patients in the first
| two days of the disease, thus demon
| strating the presence of an infectious
agent in the blood at this early period
of the attack.
Even the blood serum of patient,
passed through bacteria-proof filter,
was found to be capable of causing
! yellow fever in another person.
| ''The details of the experiments are
most interesting, but it must here suf-
fee to briefly sum up the principal
conclusions of this admirable board
| Of investigators of which Reed was
the master mind:
Il. The specific agent in the causa.
ton of yellow fever exists in the blood
of patient for the first three days of
| his attack, after which time he ceases
| to be a menace to the health of 9TH
ers.
'2. A mosquito of single species,
stegomyia faciata, ingesting the blood
/ of the patient during this infective pc.
riod is powerless to convey the disease
| to another person by its bite until
about twelve days have elapsed, but
can do so thereafter for an indefinite
| period, probably during the remainder
! of it's life.
'f3. The disease cannot be spread
! in any other way than by the bite of
the previously infected stegomyia. Ar
ticles used or soiled by patients do not
carry infection.
These conclusions pointed so clear.
| ly to the practical method of extermi
mating the disease that they we're at
once accepted by the sanitary author
! tiles in Cuba and put to the test in
Havana, where for nearly a century
and a half, by actual record, the dis
ease had never failed to appear an
nually.
Havana Free From Fever.
''In February, 1901, the chief sani-
tary officer in Havana, Major w, G.
Gorgas, Medical Department of the
United States Army, instituted meas
ures to eradicate the disease. based
entirely on the conclusions of the com
mission. Cases of yellow fever were
required to be reported as promptly as
possible, the patient was at first rigid
4 ly isolated, and Immediately upon the
\ report force Of men from the mill
tary department visited the house. All
i the rooms of the building and of the
neighboring houses were sealed and
fumigated to destroy the mosquitoes
! present. Window and door screens
were put up, and after the death or
recovery of the patient his room was
/ fumigated and every mosquito de
! stroyed. A war of determination was
also waged against mosquitoes in gen
eral, and an energetic effort was made
/ to diminish the number bred by drain
ing standing water, screening tanks
and vessels, using petroleum on water
that could not be drained, and in the
most systematic manner destroying
the breeding places of the insect.
4 When the warm season returned a
few cases occurred. but by September,
1901, the last case of yellow fever orig.
mated in Havana, since which time
the city has been entirely exempt from
the terrible disease that had there
kept stronghold for $50 years. Cases
are now admitted into Havana from
Mexican ports.sbut are treated under
screens with perfect impunity in the
ordinary city hospitals. The crusade
against the insects also caused a very
large decrease in malarjal fevers.
More reeent investigations into the
cause and spread Of yellow fever have
only succeeded in verifying the work
of Reed and his commission in every
\ particular and adding very little to our
j knowledge of the disease.
Later researches by Guiteras in Ha,
vana, BY the Public Health and Marine
4 HospitaI Snrviea in Vera f.rl11 and