LIVE POLIO IRUS VACCINES

Immunological and Epidemiological Effectiveness of Live Polio Vaccine 497
per 10000
20,0
15,0
10,0
5,0
5,5 5,6
Formn of _
dis ca e
sp in al
facialis
children
O- 4 years)
paral y tic
(childr(. n
5 -15 yearS)
y- ndex o/ morbidliy per 100000 alnong uaccilnaed;
.;~. . .. . ._ , tlntl(1r.t:i// a/r
FIG. 3. Distribution of 24 spinal paralytic and facialis paralytic
cases of poliomyelitis among vaccinated with live vaccine and unvaccinated
persons in Pskov region.
CONCLUSIONS
1. The live poliomyelitis vaccine made from
attenuated Sabin strains which we studied is
completely harmless and carries no threat of
the vaccine strains reversion to a more virulent
state.
2. Mass immunization by this method is extremely
convenient and simple and ensures the
widest possible coverage of the population within
a very short period-two or three weeks in each
cycle of vaccination.
3. The absence in the vaccinated children of
any general or local reactions, which differ in
frequency from similar symptoms in the uninoculated
external control groups, provides
every basis for sharply reducing the list of
contra-indications to the use of live vaccine when
other inoculations are being carried out.
4. The high degree of epidemiological effectiveness
of the live vaccine, shown by our observations
in 1959 in four Republics, fully justifies
the proposal to cease further use of the less
effective Salk vaccine and to turn completely
to immunization with the live vaccine from 1960
onwards.
Only the live vaccine is capable of meeting
quickly in practice the country's demands for
an effective vaccine, in view of its cheapness and
the possibility of the largest production.
5. The quite high incidence of poliomyelitis
among contact groups of unvaccinated children
indicates the need to make administration of the
live vaccine to the largest percentage of children,
as in the case of smallpox vaccination or
diptheria immunization. Only this method of
total immunization, carried out under strict
State control, will enable us to solve the most
important task of the gradual elimination of the
reservoir of wild pathogenic strains, and the
suppression of their circulation, leading inevitably
in these circumstances to the eradication of
poliomyelitis as a dangerous, large-scale infection
of children.
6. For the forthcoming mass immunization, it
will be advisable to make three administrations
of the live vaccine in accordance with the following
optimum schedule: the first inoculation
with a monovaccine of Type 1, the second with
a divaccine of Types 2 and 3, the third with a
trivaccine of Types 1, 2, and 3, administered