LIVE POLIO IRUS VACCINES

526
Efficacy-Field Evidence
TABLE 7. DEVELOPMENT OF ANTIBODIES IN INDIVIDUALS FED CHAT AND Fox
ANTIBODY TITER
CHAT
DAY OF EXAMINATION
0 30 60 110
II
Fox
DAY OF EXAMINATION
O 30
80
>512
256-512
64-128
16-32
4-8
0
4
5
14
3
33 7
4 6
6
3 3
4 3
6 3
7 4
25
3
6
7
3
2
3
16
6
3
All 33 33 24 25 25 24 25
lasted six to 12 days in each province. It was
carried out in separate provinces on fixed days.
Management of the vaccination campaign. On
predetermined days, the vaccine, packed in containers
with dry ice, was dispatched by car to
the provincial capitals. The instructions recommended
that the dilution of the vaccine in saline
be performed at the Provincial Public Health
Laboratories. For the Type 1 vaccine, the dilution
was 1:500, i.e., 200,000 TCID,, per ml.;
for Type 3, it was 1:1000, i.e., about 100,000
TCID 50 per ml. The diluted vaccine was then
placed in containers with ordinary ice and sent
by car to each vaccination point. It was advised
that the diluted vaccine be refrigerated and
used for inoculation during the first 48 hours
after dilution. Samples of the diluted vaccine
were collected at the vaccination points, and the
titer of the virus was examined in our laboratory.
Eight samples were examined, all with
satisfactory results.
The dose of vaccine to be given orally was
1 ml. It was added to 4 ml. of distilled water
with 10 per cent glucose. The proportion of
persons vaccinated varied in the different provinces
from 63 to 99 per cent. Altogether,
7,130,000 people were vaccinated with Type 1,
i.e., 83.5 per cent of the registered children in
the age group from six months to 15 years. A
total of 6,250,000 persons was vaccinated with
Type 3, corresponding to 75% of those registered
(85-94 per cent of those who received
the Type 1 vaccine).
It was decided that those who did not receive
the vaccine during this campaign would be
vaccinated at a later date. All children from
six months to 15 years will be vaccinated with
Type 2 in November of this year.
In connection with the vaccination campaign,
I would like to discuss some of the results of
our virologic and serologic investigations carried
out in three provinces.
The investigations in Warsaw were conducted
at the State Institute of Hygiene. The material
was collected in three homes for children. The
group was composed of 160 children, aged one
to three years. Samples of feces were collected
and examined before vaccination. The procedure
was repeated 10 to 14 days after vaccination
with Type 1 virus, as well as 10 to 14 days after
the administration of Type 3 virus. The results
obtained are shown in Table 8.
The table indicates that before vaccination
Types 1 and 3 virus were isolated in 3.1 per
cent. Type 2 virus has not been isolated at all.
A cytopathogenic agent was isolated in 0.6 per
cent. After the administration of the vaccine
containing Type 1 strain, the virus was isolated
from feces in 55.1 per cent. This percentage
amounted to 66.9 when Type 3 virus was given.
It should be emphasized that the percentage
of isolated strains varied rather considerably
in the different homes. In general, the Type 3
virus was isolated in a higher percentage of
cases than Type 1 virus. Serologic investigations
have not been completed as yet; hence the results
are not given here. Analogous studies were
carried out in the Public Health Laboratory at
Lublin.
The material was collected from children aged