LIVE POLIO IRUS VACCINES

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Discussion
Discussion~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Blood specimens were taken as follows: (1)
immediately before feeding with virus; (2) the
second specimen was drawn about six to eight
not have my original data sheets with me, so I
cannot say exactly how many of the women were
pregnant during this study. As I recall, it was
hours after administration of virus; (3) eight certainly not over one dozen. It is very difficult
additional samples were taken at approximately to estimate at any one point how many given
12-hour intervals, on four and a half to five consecutive
women are pregnant. They do not always tell
days; (4) four to six weeks after the you; they do not always know. Likewise, be.
Type 1 virus was received, further blood specimens
cause of the lack of these data sheets, I do not
were drawn from each child, who was then
immediately fed Type 3 attenuated poliovirus.
Blood samples of 5 to 6 ml. were drawn from
know whether the women were excreting or not.
As far as I know, no attempt was made to isolate
virus from the products of conception.
head veins of the children. The serum and the
clot were investigated separately. If necessary,
Dr. Vonka can give more details about the
method used.
The available results show that no virus was
found in any blood sample taken in the course
of four and a half to five days after feeding with
about one million TCD5o of LSc attenuated
poliovirus strain.
More detailed information on this investigation
may be obtained from Zácek and his co-workers
in our Institute for Sera and Vaccines in Prague.
The results will be published as soon as possible.
As you can see, there is evidence of a marked
difference between the results presented by Dr.
Kleinman and our results. However, it may be
because we finished the samplings too early.
Finally, as an officer of the Public Health
Service, I should like to reiterate the philosophical
remark of Dr. Kleinman, who is also a
public health officer: that the main purpose in
this study of viremia is to determine not whether
it occurs or not, but whether it is harmless for
human beings or not.
DR. PLOTKIN: The reason for my question was
that we have been unable, in triple-negative infants,
to obtain uniform success with trivalent
vaccine in contrast to success with monovalent
vaccine, admittedly with different strains. However,
and this point has been implied by Dr.
Paul already, when one looks at the data of
Dr. Cox and Dr. Kleinman, the response of those
who were triple negative before ingestion of
trivalent vaccine is certainly inferior to the results
in the same type of people using monovalent
vaccine.
For example, in Dr. Cox's paper there was
conversion from triple negative to triple positive
in 49 per cent of triple negatives. In Dr. Kleinman's
study, whereas children fed monovalent
vaccines converted in 18 out of 18 cases, those
fed trivalent vaccine converted to triple positive
in only seven out of 16 cases. Consequently, I
think that there is a difference between monovalent
and trivalent vaccine and that the difference
can be shown by isolating the triplenegative
children from the others.
DR. KLEINMAN: In reply to Dr. Plotkin's question,
I am sure he knows that on the basis of our
study we cannot say definitely whether the monovalent
is better than the trivalent vaccine. For
Type 3, there appears to be little difference in
the efficiency of a monovalent preparation as
compared to a trivalent preparation.
The point that I wanted to make, from the
public health standpoint, was that the trivalent
preparation does appear to be a promising public
health and immunological tool, with its greatest
deficiency appearing in response to the Type 2
component.
I am sorry I do not have the answer to Dr.
Plotkin's second question. I regret that I do
DR. PREM: Yesterday I reviewed the data I
have concerning the three abortions that 1 reported
among the pregnant women who had
been vaccinated with either monovalent or trivalent
vaccine. Two of these three were women
who were reported in Dr. Kleinman's study presented
at the fifth session.
Two of these three women had negative antibody
titers before feeding. They responded to
feeding with significant antibody increases. This
negative pre-feeding status suggests that virus
excretion in the stools and viremia did occur
if the viremia data presented by Dr. Bauer can
be applied-that is, viremia is present pre-