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Raj Narain, Kul Bhushan & M Subramanian: Indian J TB 1961, 7, 1-15.

In all, 1,259 students aged 11-19 years from three boys high school of Bangalore, formed the study group. They were tuberculin tested with 1 TU RT 23 containing Tween 80. Boys with a reaction of 13 mm or less to tuberculin test and willing for BCG vaccination were allocated in 3 groups: (i) to be vaccinated with Madras vaccine (211), (ii) to be vaccinated with Danish Vaccine (236), (iii) control with saline injection (231) (placebo). Strength of Madras and Danish vaccines used was same, 0.075 mg per dose. After 3 months of vaccination, second tuberculin test with 1 TU RT 23 with Tween 80 was given to 575 boys included in both the vaccinated groups and in the control group. A follow up at one year after vaccination was done among 328 boys, who were again tuberculin tested.

The analysis of data shows that the mean size of post-vaccination tuberculin test induration among Madras BCG vaccinated group was 11.8 mm and among Danish BCG vaccinated group, it was 11.9 mm, the standard deviation were 3.8 and 4.5 mm respectively. The above differences between the 2 vaccinated groups were not-statistically significant. Similarly, the post-vaccination allergy in the two BCG vaccinated groups at the end of one year was not-significantly different. The mean size of the scar produced by two vaccines were also smaller. The post-vaccination allergy among persons whose pre-vaccination tuberculin induration was 9 mm or more to 1 TU RT 23 with Tween 80, did not increase by more than 4 mm after vaccination. While the group whose pre-vaccination tuberculin induration was below 9 mm, had an increase of post-vaccination allergy of a little over 8 mm. It is concluded that the allergy producing capacity of the Danish and Madras vaccines was not different.


Kul Bhushan: Proceed 18th Natl TB & Chest Dis Workers Conf, Bangalore, 1962, 286-89.

In view of the variable and low levels of post-vaccination allergy elicited in the Indian Mass BCG Campaign vaccinated groups as observed by WHO and Indian BCG Assessment Teams, some studies were carried out to investigate some of the factors considered having influenced the levels of post-vaccination allergy. The reasons were potency and storage of vaccine, techniques, interval between vaccination and retesting and tuberculins used. Potency of the vaccine: Madras vaccine was compared with Danish vaccine. The retest done at 3 months with 1 TU RT 23 showed 11.8 mm induration with Danish and 11.9 mm with the Madras vaccine. Test done after one year with 20 TU induration was 18.3 mm for both the vaccines. It is reasonable to assume that the vaccine produced at Madras is as potent as Danish vaccine. Storage of vaccine: A comparison of post-vaccination allergy in respect of storage of vaccine by the ICMR Assessment Team and by Mass Campaign Teams was carried out in five groups of villages in the neighbourhood places where five BCG teams were working in Tamil Nadu. The non-reactors were vaccinated randomly by vaccines stored by either team and with the placebo III group as control. The retest done after 3 months showed that in all the five groups combined the mean size of indurations vaccinated with vaccine stored by Assessment Team were more in the vaccine stored by Mass Campaign Team. The loss of potency was 0.7 mm per week in vaccine stored by Assessment Team and 1.5 mm per week stored by Mass Campaign Team. Techniques: The above study was extended to five more groups vaccinated and tested by the Mass Campaign Team. Assessment Team also vaccinated separate groups with the same vaccine and tested on the same day. Mean size induration for groups combined was higher for assessment team but not significant. So, the techniques do not seem to make much difference. Interval between vaccination & retesting: Analysis of data collected on post-vaccination allergy in the groups vaccinated by the Mass Campaign Teams retesting according to intervals showed that the mean size induration decreased with the increase in interval between vaccination and retesting from 1-20 months. Thereafter, it rose again. These results indicate a tendency for the allergy after vaccination to wane with passage of time. The rise is presumably due to super infection or difference in batches of vaccine. In the third year (not included in this paper) greater proportion of people had bigger reactions. Besides, tuberculin used for retesting is also found to give differences in mean size induration. Tuberculin 5 TU RT 22 gave larger reactions than 1 TU RT 23 with tween, the differences were above 3 mm.

It can be concluded that at present Madras vaccine is satisfactorily potent, the post-vaccination allergy is influenced by storage of vaccine, by interval between vaccination and retesting and type of tuberculin used for eliciting the allergy. Technique of testing, reading and vaccination may not influence the results. Under Indian climatic conditions the liquid vaccine should not be used for more than 2 weeks. There is a need for Freeze-Dried vaccine.


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.