LIVE POLIO IRUS VACCINES

Recent Experience with Lederle Trivalent Oral Poliomyelitis Vaccine
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TABLE 2.
POLIOVIRUS ANTIBODY STATUS
GROUP: 67 SERO NEGATIVES OF 123 PERSONS FED
IN ST. JOSEPH'S ABBEY, WORCESTER, MASS.
DOSE: 2 ML ORAL TRIVALENT POLIOVACCINE (7-12: 38-803)
PRE-VACCINATION
POST-VA CINATIC
DATE: 1959
TOTAL RESIDUAL NEGS. TOTAL NO. OF
NEGATIVE NO. OF NO. Tn TYo _ NO. COMPLETE
TO TYPE PERSONS NEGS. 1 2 3 2&,3 NEGS. CONVERS ION
1 10 10 0 10
2 8 8 1 1 7
3 13 13 1 1 12
1 & 2 10 20 1 1 9
1 &3 6 12 0 6
2&3 8 16 0 8
1,2, k3 12 36 7 1 8 4
TOTALS 67 115 0 9 1 1 11 56 (83.6%>
conversion to Type 2. The conversion rates were
100, 74, and 95 per cent, respectively, for poliovirus
Types 1, 2, and 3. This information and
the booster response rates in persons possessing
various levels of antibody before feeding are
summarized graphically in Fig. 2.
Here you see pretty much the same thing. I
do not know, but it may be because we may have
introduced a bit more of Type 1 into this particular
batch, since here we obtained a conversion
rate of 100 per cent for Type 1, that is, 38 out
of 38, 28 out of 38 for Type 2, and 37 out of 39
for Type 3.
These other charts are practically identical to
what we saw previously in the Cuban data.
In this group we are talking about those individuals
who had detectable antibodies at a level
of less than 1:16. Here are indicated those
people who had antibody levels of 1:32, but less
than 64. These had antibody levels of 128 but
less than 256, and here are those with antibody
levels of 512 but less than 1024.
Some of these persons actually had antibody
levels higher than 1024, but we did not carry our
tests higher than that because we did not think
it necessary.
These sera are on hand, and some day, when
we have more time, we intend to find out just
how high these antibody levels did go.
Here you see each of the percentage conversion
rates and here you have the actual figures in
terms of ratios.
Group 3, the largest of the three study groups,
consisted of 933 persons all but 95 of whom were
over 18 years of age. Included in the 933 are
188 persons who received the 2 ml. dose of trivalent
oral vaccine described in our previous
report contained in the British Medical Journal
of October 1959.' With few exceptions this group
represented Lederle Laboratories personnel and
members of their families.
A single lot of trivalent vaccine was used to
vaccinate 652 persons, including the 188 mentioned
above, and 275 others received vaccine
from a second lot. Six individuals were fed
from a third lot.
Pre-vaccination sera showed that 485 persons,
or 52 per cent of the 933 volunteers, were without
antibody for one or more types of poliovirus
and the distribution and combinations of antibody
gaps are indicated in Table 3. Here you see
the breakdown of the antibody negatives. We