Evening star., 1946-01-20
Scientist Describes
Use Of Eggs 10 Make
New Flu Vaccine
By THOMAS r. HENRY.

An influenza vaccine, active
against all three known types of
this epidemic disease and which
appears to give adequate protec-
tion for as much as go weeks, was
produced under the direction of
the Office of Scientific Research and
Development during the war and
now can be made in sufficient
quantities to protect the whole
world.
The achievement up TO now has
been considered q war secret. The
methods of producing the new vac
cine were described before the
Washington Academy of Sciences by
DR.. William M. Stanley of the
Rockefeller Institute who had
charge of the work.
The influenza vaccine available
when the United States entered the
war was so uncertain in its effects
that practically no reliance could
be placed on it as protection. Re-
calling the great epedemic which
killed 100000 in 1918, this was
one OF the first problems to which
the medical branch of the war
science organization turned its at
tention in 1912
Plant Virus Experts.
DR.. Stanley and his associates
were experts on plant viruses and
had succeeded more than u years
ago in isolating in almost pure form
the almost infinitestimably minute
organism responsible for the tobacco
mosaic disease. The causatiye
organism of flu falls in the same
general class. Although they had
no experience in animal viruses
they were put to work on the
problem.
They soon determined the major
difficulty. The flu virus presum-
ably had been isolated in 1888 and
has been the basis of previous
taccines. The scientists soon found.
however, that the amounts of actual
virus in the preparations had
varied enormously. Some samples
OF the existing vaccines probably
had next to none, and consequently
could not be expected to give any
prftection.
BY methods developed in their
plant work they were able to de-
termine the exact shape and size
of the organism-a tiny ball about
R00-millionths of millimeter in
diameter. They made pictures of
1t with an electron microscope
Hitherto, there had only been
guesses as to its shape and ap-
pearance. They were able to OBJ
tain. concentrations of these in
finitesimably minute balls with
scarcely any extraneous material.
Grew Virus in Eggs.
Then they developed methods of
growing the virus in incubated
chicken eggs which were many
times more effective than any
known before. So great was their
success in this line that one egg
will now yield approximately three
doses of the vaccine, at a cost of
about 10 cents. One dose appears
to be enough to immunize a person
for year.
They also found that the potency
of the vaccine was greatly en-
hanced by new methods of inacti-
waiting it.
The organism, they found, had
more of the characteristics of a
tiny animal than the plant viruSes
with which they previously had
worked.
Type A influenza and Type B,
the disease responsible for the pres
ent mild epidemic, act like two en-
tirely different maladies, they found,
since the virus of one gives no pro-
lection against casuative organism
of the other.
Lack Conclusive Evidence.
The efficacy of the new vaccine
can be judged at present only by
the increase of protective anti
bodies in the blood. There has been
no great epidemic against whose
spread it could be tested. The anti
body count, however, is considered
reliable criterion of the efficacy
of other vaccines
There is no conclusive evidence,
DR.. Stanley says, that any of the
three flu types now known was re-
sponsible for the 1918 epidemic. The
virus was unknown at that time.
But with the present methods of
concentration and deactivation, he
says, it is almost certain that a
potent vaccine against the 1918 type
could be made in vast quantities
a.. Il,