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120 |
ASSESSMENT OF BCG VACCINATION IN INDIA; THIRD REPORT |
Kul Bhushan: Indian J Med Res 1960, 48, 406-17. |
Under the auspices of the Indian Council of Medical
Research, a third assessment of the mass BCG campaign in
India was carried out from 1955-58. It is a continuation
of the work started by the WHO, of evaluating the level of allergy
among groups vaccinated in the campaign. WHO team used 5 TU RT 14,
20, 21, while the present assessment team used 5 TU RT 22.
A total of 18,367 school children distributed over 262 schools in
169 different localities were retested for post-vaccination tuberculin
sensitivity. The groups were vaccinated in mass BCG campaign
with 91 different batches of vaccine produced in Madras. The interval
between vaccination and retest varied from 1½ to 42 months.
The mean size of reactions varied from 8.3 to 16.6
with overall mean of 12.5 mm. Less than 10% of the mean values
were under 10 mm and less than 10% over 15 mm. Analysis also showed
that BCG vaccination was responsible for an increase of 6-7 mm
in the mean size of reaction over the pre-vaccination level of the
non-infected. One third of the groups had their sensitivity increased
upto 6 mm and two third by 7-11 mm. Comparing with the highest attainable
degree of tuberculin sensitivity in the infected 1/3rd of the vaccinated
group fell short of it by 5-9 mm, whereas 2/3rd were within 4 mm
of this level. There is no appreciable difference in the post-vaccination
allergy according to the state and prevalence of non- specific tuberculin
sensitivity. However, there is an increase in allergising capacity
of the BCG vaccine after introduction of modifications in the production
procedures in 1955 and again in 1956 in the BCG Laboratory at Madras.
Waning of allergy upto 20 months after vaccination and boosting
thereafter probably due to super infection was also observed. Findings
show that a large proportion of the vaccinated groups retested have
achieved attainable allergy with the vaccine used. In view of the
above, there is an urgent need to produce Freeze-Dried vaccine than
the present liquid vaccine for achieving high levels of allergy.
Freeze-Dried vaccine holds out promise for
use in the mass BCG campaign. A continued and expanded research
is needed into the protective value of BCG vaccination with the
level of allergy which the mass campaign can produce under the epidemiological
circumstances existing in India and other technically developed
countries.
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KEY WORDS: BCG VACCINATION, ASSESSMENT, TUBERCULIN
SENSITIVITY, TUBERCULIN ALLERGY, LIQUID BCG, FREEZE-DRIED BCG. |
123 |
TRIAL ON EXPERIMENTAL BATCHES OF FREEZE-DRIED BCG
VACCINE PRODUCED AT GUINDY LABORATORY |
Kul Bhushan: Bull Dev Prev TB 1962, 9, 16-19. |
Government of India set up a plant for producing
Freeze-Dried vaccine at BCG Vaccine Laboratory, Madras in 1959.
Before releasing the freeze-dried vaccine to the mass campaign it
was necessary that it is subjected to various tests. This paper
deals with two such trials. The first study planned in this connection
was for the assessment of allergising properties of two lots
each of four batches of freeze-dried vaccine. The second study
was to investigate the stability of two lots of a batch of
freeze-dried vaccine in relation to storage at different temperatures
for varying periods.
The results indicate that though the liquid vaccine
has on the whole produced slightly higher allergy than the freeze-dried
vaccine, the level of allergy achieved with the freeze-dried
vaccine is quite adequate. Levels of post-vaccination allergy
in the lots containing glutamate and tween 80, show that increase
in storage temperature has resulted in higher loss of potency of
vaccine. No definite trend is indicated regarding the lots containing
glutamate alone.
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KEY WORDS: FREEZE-DRIED BCG, CLINICAL TRIAL,
POTENCY, STABILITY. |
133 |
FREEZE-DRIED BCG VACCINE SEALED IN PRESENCE OF NITROGEN |
Kul Bhushan, GVJ Baily, SS Nair, KT Ganapathy &
Vijay Singh: Indian J Med Res 1975, 63, 1335-43. |
The Freeze-Dried BCG vaccine manufactured in India
is sealed under vacuum. This though adds to its stability involves
expensive production procedures. Sealing in presence of nitrogen
is both simpler and economical. Before producing this vaccine for
use on a large scale, it was considered necessary, to study the
influence of storage at higher temperatures on the allergy inducing
capacity on the basis of the size of local lesion and viable
counts of Freeze-Dried BCG vaccine sealed either in vacuum or in
the presence of nitrogen. For this, half of the ampoules of a batch
of vaccine prepared in Madras BCG Vaccine Laboratory were sealed
in vacuum and the other in presence of nitrogen. Randomly
selected ampoules of both types of vaccine were exposed to 37o and
44o for 2, 6, and 18 weeks and another set at 4oC for 18 weeks.
Two batches of liquid BCG vaccine were made as controls: 16 types
of ampoules thus obtained were randomly repeated 5 times according
to Standard Lattice Design. About 3000 school children without BCG
scar, aged 5-14 years In Bundi and Kota districts of Rajasthan were
vaccinated as per the study design. post-vaccination allergy with
5 TU RT 22 by measuring the size of vaccination lesions was recorded
3 months later. Viable counts on samples of ampoules from Freeze-Dried
BCG vaccines exposed differently were done in the production laboratory
after 18 weeks of storage.
The vaccine in 16 types of ampoules was significantly
different. Liquid BCG vaccine resulted in higher level of allergy
and larger vaccination lesions than Freeze-Dried BCG vaccine sealed
under either method. The study has shown that Freeze-Dried BCG
vaccine sealed under either method vacuum or nitrogen, gave satisfactory
level of post-vaccination allergy and induration size of vaccination
lesions, provided the vaccine was preserved at 4oC. Storage at 37o
for more than 2 weeks and even 2 weeks storage at 44oC affected
both types of vaccine badly as shown by post-vaccination allergy
and viable counts. However, decrease in viable count with time and
temperature was more pronounced in vaccine sealed in presence of
nitrogen. Hence, there is a need to provide cold chain facility
for Freeze-Dried vaccine all throughout the period.
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KEY WORDS: LIQUID BCG, FREEZE-DRIED BCG. |
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