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125 |
BCG WITHOUT TUBERCULIN TEST |
GD Gothi, Kul Bhushan, SS Nair & GVJ Baily: Proceed
19th Natl TB & Chest Dis Workers Conf, New Delhi, 1964, 138-62. |
In the BCG Mass Campaign low outputs and coverages
of BCG vaccination done after tuberculin test were due to slowness
of the campaign because of two visits to an area, the fear of two
pricks and tuberculin tested absenting themselves from reading of
the test. It was thought that if BCG vaccination could be given
without prior tuberculin test and without causing any complications
then the speed of work and outputs could be more than doubled and
coverages improved appreciably. For this, the following three studies
were carried out: In the first study 1,891 persons belonging
to a rural population were randomly divided into four groups (i)
those tuberculin tested and vaccinated, (ii) tested but not vaccinated,
(iii) not tested but vaccinated, and (iv) neither tested nor vaccinated.
Induration site of tuberculin test and vaccination were read on
the 3rd, 6th and 90th day. Later on, another tuberculin test was
done on the 90th day and read 3 days later. Both axillae were examined
on 0, 14th and 90th day and X-ray pictures were taken on 0 day,
90th day and after one year. Tuberculin indurations on 3rd day were
compared with BCG induration on 3rd, 6th, 14th and 90th day. Majority
of tuberculin reactors had large BCG indurations upto 14th day.
By 90th day very few persons have large indurations left. Among
non-reactors also large BCG reactions were seen in 25%-53% of the
persons. There were no differences as regards to the size of lymph
nodes (regional reactions) between reactors and non-reactors; neither
was there any evidence of exacerbation of existing disease nor any
flaring up of dormant foci (Primary complex) in the form of new
disease as shown by X-ray.
In the second study out of 1,520 persons
from 4 villages, 1,186 were both tuberculin tested and simultaneously
vaccinated. Examination of local reactions daily from one to
nine days, on 19th and the 29th day, confirmed the findings of first
study with regard to the local reactions. In this study neither
axillae were examined nor X-ray pictures taken. In the third
study, influence on acceptability of direct BCG vaccination
due to large local reactions was tested. Twelve villages in Gubbi
taluk of Tumkur district were taken in pairs. Vaccination of 2nd
village of each pair was done after 1-4 weeks of the vaccination
in lst village to observe the influence of BCG reaction on the people.
Vaccinations were given to 5363 (64.2%) persons from the total registered
population with Madras liquid vaccine. The large local reactions
showed no adverse effect on the acceptability of BCG vaccination
in the neighbouring villages, rather a slight improvement in BCG
vaccination coverages with time was seen.
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KEY WORDS: RURAL POPULATION, DIRECT BCG VACCINATION,
APPLICABILITY. |
126 |
TECHNICAL ASPECTS OF BCG VACCINATION CAMPAIGN |
Kul Bhushan: Bull Dev Prev TB 1965, 11, 31-35. |
During the 7th All India BCG Conference held at
Ahmedabad in February 1965 various points regarding the technical
aspects of BCG Campaign were put forward by the author of this article.
The issues discussed were related to specific age group to be vaccinated;
direct vaccination; vaccination of new-borns; techniques of testing,
reading and vaccination; preservation of biologicals, Freeze-Dried
vaccine; pilot and research studies; assessment and training.
Some of the suggestions given on the above aspects
described briefly were: (1) Only 0-20 years might be taken up because
that was the most vulnerable age group for infection from the natural
sources. (2) Direct BCG vaccination in 0-20 years age group
could be carried out in the first round followed by vaccination
of population below 7 years of age (0-6 years) in the subsequent
rounds. (3) Infant vaccination practiced at that time in some of
the major cities only, would not contribute greatly to the control
of tuberculosis unless it is extended to the rural areas also. (4)
Results of vaccination should be exceedingly good provided vaccine
was maintained properly, used within 2 weeks of manufacture, shaken
well before opening, a drop ejected out before vaccination and proper
dosage injected correctly. (5) The vaccine must be kept under refrigeration
during storage, transport and use. (6) The personnel engaged in
the use of Freeze-Dried vaccine had to be trained properly
in its aseptic reconstitution. (7) Operational studies in respect
of BCG work in cities; practicability and feasibility of setting
up training centres in the states, assessment of programme by the
states etc., were required to be undertaken. (8) Uniformity of techniques
and procedures of BCG vaccination and proper assessment of Mass
BCG Campaign by an independent agency would be required. The author
in his article also stressed that no changes should be brought into
operation without assessment.
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KEY WORDS: BCG VACCINATION, MASS BCG CAMPAIGN,
DIRECT BCG VACCINATION. |
128 |
ASSESSMENT OF POST-VACCINATION ALLERGY AMONG THOSE
BCG VACCINATED WITHOUT PRE-VACCINATION TUBERCULIN TEST |
Kul Bhushan, SS Nair & KT Ganapathy: Indian
J TB 1970, 17, 18-31. |
The conventional methods of assessment of post-vaccination
allergy by doing tuberculin testing among the vaccinated group are
inapplicable in case of BCG vaccination without prior tuberculin
test (Direct BCG). Because of obvious technical and operational
advantages of direct BCG vaccination a search for a method of technical
assessment of BCG vaccination is important. Hence, a study was
carried out by the BCG Assessment Team of National Tuberculosis
Institute in Tumkur district of Mysore state where Mass BCG Campaign
was going on. Four groups of persons aged 0-20 years, each group
belonging to two BCG Technicians area and vaccinated one day prior
to visit of assessment team, were randomly selected. Besides, persons
(0-20 years) from 2 unvaccinated villages of adjacent area were
included as control groups. All persons were registered simultaneously
tuberculin tested with 1 TU RT 23 and 5 TU RT 22 within 24
hours of BCG vaccination (for pre-vaccination allergy) and retested
with tuberculin 5 TU RT 22 at the end of 3 weeks and 3 months (for
post-vaccination allergy). The four vaccine groups were vaccinated
with vaccine batch Nos. 977, 978, 981 and 984 respectively. Classification
of the directly vaccinated persons into previously infected and
non-infected by tuberculin test administered within 24 hours of
vaccination and about 12 weeks later, elicitation of post-vaccination
allergy only among the non-infected, has been considered as the
Reference Test for judging the suitability of other methods of assessment
studied. The main findings are: (1) The Reference Test showed that
the four batches of BCG vaccine used had induced varying levels
of allergy. (2) Assessment based on the mean size of post-vaccination
reactions among 0-4 years age group, which consists predominantly
of previously non-infected persons, showed a different pattern of
differences between the four batches of vaccine as compared to the
Reference Test. Moreover, to get adequate number of children aged
0-4 years, it will be necessary to cover a comparatively large population.
(3) The method of using the mean size of post-vaccination reactions
among those classified as non-infected on the basis of vaccination
reactions of size 0-13 mm at the site of BCG vaccination on the
4th day of vaccination showed results similar to the Reference Test.
But this method has only a marginal operational advantage over the
Reference Test. (4) Using size of induration at the site
of vaccination on 21st day of vaccination did not give the same
results as the Reference Test. Operationally this method would have
been most suitable as it involved only one visit to the group. (5)
Differences between mean size of post-vaccination tuberculin reactions
among directly vaccinated persons and mean size of (natural) allergy
in reactors among neighbouring unvaccinated areas showed the same
results as the Reference Test. This method has the operational advantage
but needs further investigations. (6) Tuberculin testing of all
directly BCG vaccinated persons including the natural reactors about
12 weeks after vaccination compared favourably, with the reference
method, as the tuberculin reactors contributed less than 1 mm over
and above the allergy in the vaccinated non-reactors . This method
would be useful when rate of tuberculin reactors is less than 20%
in 0-20 years age group and their mean size is also less than 20
mm. Operationally, it is a simpler method next only to No.4 above.
Further investigations are considered necessary for final selection
of this or any of the other methods.
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KEY WORDS: BCG, POST-VACCINATION ALLERGY, ASSESSMENT,
DIRECT BCG VACCINATION. |
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