LIVE POLIO IRUS VACCINES

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TOPIC III. EFFICACY. (A) LABORATORY
EVIDENCE
1. THE DEVELOPMENT AND PERSISTENCE OF POLIO
ANTIBODIES, MEASURED BY DIFFERENT METHODS
OF NEUTRALIZATION TEST, IN YOUNG ADULTS
FED WITH 100,000 TCD 5 o OF TYPE 3
ATTENUATED VIRUS
V. VONKA, E. SKRIDLOVSKÁ, J. JELINEK, AND J. DUBEN*
228
DR. VONKA (presenting the paper): Differences
in the quality of antibodies in the
course of poliomyelitic infection have been repeatedly
discussed. Ward 1 reported on the different
influence of the quantity of virus, included
in the virus antibody assay, on the titer of antibodies
in the acute and convalescent sera of
patients with paralytic polio. Brunner and
Ward 2 found later that the virus-acute-antibody
complexes dissociated more readily at a low pH,
than complexes of virus and antibody from the
convalescent stage of infection. Sabin ', using
pH and CP tests in his studies on polio antibody
development, suggested that, in the early stages
of poliomyelitic infection, the antibodies of low
avidity were formed, being converted in the
further course of infection to high avidity antibodies.
He expressed the view that the method
of the pH test was the most suitable for low
avidity antibody estimations. These antibodies
could not be detected by the routine CP test, by
means of which only high-avidity antibodies
forming with virus complexes, more resistant
to the influence of dilution, could be demonstrated.
In persons possessing antibodies in their
pre-immunization samples of sera, Sabin found
earlier inereases in high rather than in low
avidity antibodies, and presumed a qualitative
change in antibody character from low to high
avidity as the first step in the antibody development
in these individuals.
In our last paper,' we compared the results
obtained with the simultaneous use of both the
pH and CP tests in performing serological surveys
and in studying the antibody response in
persons vaccinated with inactivated and live attenuated
poliovirus vaccines. On the basis of an
analysis of the decrease of antibodies in the sera
of infants in the first months of life, we draw the
suggestion that the presence of pH antibodies
only, did not necessarily signify antibodies of low
avidity, but rather, low levels of antibodies not
demonstrable in the less sensitive routine CP
test.
In order to obtain more information about the
antibody development and the changing nature
of antibodies in the course of poliomyelitic infection,
we vaccinated a group of young adults with
Type 3 attenuated poliovirus and investigated the
polio antibodies in a series of serum samples,
taken at different intervals after virus was fed,
using different methods of neutralizing antibody
estimation. Types 1 and 2 antibody response
was studied simultaneously.
MATERIALS
A group of 22 young adults were fed with
about 100,000 TCD 50 of Type 3 attenuated poliovirus
(Sabin strain), Leon 12, a 1 b. These subjects,
between the ages 15 to 18, were selected on
the basis of a preliminary serological investigation
from the total number of about 60, all living
in a nurses' quarters. The standard of hygiene
* Dr. Vonka and Dr. Skrídlovská (Department of
Virology, Institute for Sera and Vaccines, Prague);
Dr. Jelínek (Institute for Epidemiology and Microbiology,
Prague); Dr. Duben (Hygiene and Epidemiology
Station, Havlíckuv Brod.).