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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.

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.

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.

KEY WORDS: BCG, POST-VACCINATION ALLERGY, ASSESSMENT, DIRECT BCG VACCINATION.
 
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