LIVE POLIO IRUS VACCINES

Further Experiences with Oral Poliomyelitis Vaccines in Minnesota 313
TABLE 1. PARTICIPANTS BY AGE AND VACCINAL STATUS (SALK)-GROVE EAST STUDY, 1959
SALK VACCINE STATUS
TOTAL NO.
MIEAN AGE
NoNE
ONE
DOSE
T\\o
DosEs
THREE
DosEs
Four
DOSES
Childrern
111
3.3 years
10
o
27
613
11
Fathers
. 3
27 years
8
6
17
21
Mothers
55
26 years
3
13
36
2
viremia studies were collected after the trivalent
feeding in the trivalent group and after the Type
3 feeding in the monovalent group.
It should be noted here that the feeding unit
was the family and not the individual. That is,
all the participating members of a family always
received the same type of feeding.
It is also apparent from Table 2 that there was
a period from the first day through the 52nd
when those in the trivalent group received
placebo while those in the monovalent group were
receiving Type 2 and Type 1 vaccine in that
order. This period was a definite control period,
and its principal use in this study was to enable
one to critically compare any "reaction" illnesses
that occurred in those who received vaccine virus
with those that occurred in the participants who
received placebo.
Only two persons (A.C.K. and J.E.B.) in the
project team knew the identity of the individuals
who comprised the monovalent and the trivalent
groups. The participants thus never knew until
the end whether and when they had received vaccine
or placebo or whether the vaccine they did
receive was monovalent or trivalent. The project
team with the exceptions noted was in a like posi-
TABLE 2. OPERATING PLAN-GROVE EAST STUDY, 1959
I)AV*
TRIVALENT GROUP
MONOVALENT GROUP
1-3
4-5
21-23
24-25
50-52
53-54
57-61
77-79
80-81
First Blood and Stool
Placebo
Second Stool
Placebo
Third Stool
Trivalent vaccine
fThroat swabs and
blood for viremia
Fourth Stool
Second Blood
First Blood and Stool
Type 2 vaccine
Second Stool
Type 1 vaccine
Third Stool
Type 3 vaccine
|Throat swabs and
blood for viremia
Fourth Stool
Second Blood
* Dav 1 is February 22. 1959.