LIVE POLIO IRUS VACCINES

Minnesota Studies with Oral Poliomyelitis Vaccines
361
always prevent virus from multiplying in the
pharynx. The presence of virus in a stool specimen
collected on the fourteenth day after ingestion
of the vaccine could not be predicted from
the pre-vaccine antibody titer; however, there
seemed to be a trend that virus isolation was more
frequent when the antibody titer was less than
four for the poliovirus type isolated.
A summary of the laboratory results obtained
in eight persons for whom viremia was demonstrated
is shown in Table 7. Viremia and its
association with dose form, time of ingestion of
vaccine in relation to lunch, pharyngeal infection,
gut infection, pre-vaccine, and post-vaccine
antibody titers are all shown in Table 7. Type
1 virus was isolated from seven persons and
Type 3 poliovirus from one person. Virus was
isolated more frequently from 2.0 ml. of serum
than from 0.2 ml. of serum. In the case of
specimens Nos. 491, 511, and 576, from which
virus was isolated from 0.2 ml. of serum, isolation
of virus was attempted from the three
specimens from serum dilutions 1:100 and
1:1000. In specimen 491, Type 1 virus was detected
in the 1:1000 serum dilution. No virus
was detected in diluted serum specimens Nos. 511
and 576. It is interesting to note that specimen
576-which is person 576-reported that he had
three doses of Salk vaccine. His antibody titer
was less than four for the three poliovirus types.
In the majority of instances, the virus isolated
from the blood serum was also detected in the
oropharynx and the stool specimen. Antibody
conversion occurred for the virus isolated in all
instances except one. The dosage form, ingestion
of the vaccine before or after lunch, appeared to
have no relationship to viremia.
As shown in Table 8, the frequency of virus
isolation from the blood serum was greater from
those persons whose pre-vaccine antibody titer
TABLE 5.
VIRUS ISOLATION FROM PHARYNX OF PERSONS WITH PREVACCINE ANTIBODY TITER OF LESS
THAN 4 TO ONE OR MORE TYPES. HOUSES A AND D-RECEIVED UNENCAPSULATED VACCINE
TITER OF LESS THAN 4
NUMBER
TYPE OF PERSONS
I
II
III
1 AND
II
VIRUSISOLATED
I AND
III
II AND
III
I, II,
AND III
TOTAL NUMIBER
OF ISOLATES
NUMBER OF PERSONS
FRONf WmHOM VIRUS
WAS ISOLATED
I 5
#xo
#Xo
#X
8
3
t1 5
O
1
1
III 15
#xo xo
xo
xo
xo
X
#XO
23
7
I and II 1
o
I
I and III 3 X 0 # 0
5
2
II and III 2
_XO
3
2
I, II, and III 2
X
X
13
2
Total 33
54
*18
Summary showing day and nunimber isolated by virus types
DAY I II III TOTAL ISOLATED
# 3 8 2 5 15
X 5 8 3 11 22
0 7 6 3 8 17
Total 22 8 24 54
* Number of persons from whom virus was isolated: 18/33 or 54.5%.