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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.

KEY WORDS: BCG VACCINATION, ASSESSMENT, TUBERCULIN SENSITIVITY, TUBERCULIN ALLERGY, LIQUID BCG, FREEZE-DRIED BCG.

127
SIMULTANEOUS SMALLPOX AND BCG VACCINATION
Kul Bhushan, GVJ Baily & VB Naidu: Indian J TB 1968, 15, 52-56.

A study was carried out in Bangalore city corporation area with the following objectives; when BCG vaccination is administered simultaneously with primary smallpox vaccination to infants; (i) whether any immunological interferences take place as indicated by the development of vaccination lesion and post-vaccination allergy due to BCG vaccination and the development of the local lesion (take rate) of smallpox vaccination; (ii) whether the incidence of complications are higher among those simultaneously vaccinated and, (iii) whether the population will accept a procedure involving two vaccinations. BCG technicians and the smallpox vaccinators registered all the eligible children after house to house visit and randomly allocated to three groups. A total of 789 children aged below one year were admitted to the study. While 315 were vaccinated simultaneously with BCG and smallpox vaccines (BCG on the right arm and smallpox on the left), 255 were vaccinated with smallpox vaccine only and 219 with BCG vaccine. All 789 children were followed up on the 5th, 21st, 90th and 93rd day of vaccination. The 5th and 21st day followups were to study the development and healing of smallpox vaccination lesions, whereas the 21st, 90th and 93rd day followups were for BCG vaccination lesions. The 90th and 93rd followups were for tuberculin testing and reading.

It was found that there was no evidence of immunological interference between the two vaccines when administered simultaneously i.e., the development of lesion of smallpox vaccination among the simultaneously vaccinated group was similar to the development of the smallpox vaccination lesion among the only smallpox vaccinated group and, the post-vaccination allergy due to BCG among the simultaneously vaccinated group was similar to the post-vaccination allergy among the only BCG vaccinated group. The complications due to vaccinations were very few and similar among the simultaneously vaccinated as compared to the other respective groups. The acceptability of simultaneous vaccination was higher than BCG alone. The above study has demonstrated that BCG and smallpox vaccinations can be administered simultaneously.

KEY WORDS: SIMULTANEOUS BCG & SMALLPOX VACCINATION, ASSESSMENT, ACCEPTABILITY, COMMUNITY.

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.
 

 
  ASSESSMENT & EVALUATION  
 
 
165
EVALUATING CONTROL PROGRAMMES
J O'Rourke:Proceed 19th Natl TB & Chest Dis Workers Conf, New Delhi, 1964, 195 208 & Indian J TB 1965, 12, 87-94

Control of tuberculosis may be defined as a deliberate interference in the relationship between man and bacillus that changes favourably the epidemiological trend. Compared with the other factors at play on this relationship, the weapons available for a control programme are narrow in their range and must be used with great foresight if they are to benefit the country. Under Indian conditions, with tuberculosis ubiquitous in its occurrence, with no striking focality of infection and disease that would justify selective restricted efforts, control measures must necessarily cover the whole community and the programme must be maintained for a long time. Control will be a slow process, demanding continued investment of men and supplies, persistent and careful organisation. There is no short cut.

The assessment of programme (performance) requires similar approach. Evaluation (impact) must concern itself initially with examining the operational and technical performance, enquiring in detail how the immediate achievement has compared with the forecast, as changes in prevalence are expensive to detect and may not be due to control measures applied. In general, supervision asks if a rule is obeyed: assessment enquires whether it has really been obeyed, whether it can and should be obeyed and whether there might be a better rule. For e.g. evaluation of BCG campaign encompasses the whole series of activities undertaken and not only confined to occasional surveys of post-vaccination allergy. It is important for curative work also. Pilot evaluation report of Anantapur programme after one year in 1962 is given as an example of simple assessment. A great majority of patients diagnosed at district centre came from outside, while at peripheral hospitals 90% came from the same taluk. Treatment completion were 38% to 40% among patients belonging to the same town and very low among those living outside. This gives importance of Case-finding in peripheral centres. Referral also played very little part. The accuracy of diagnosis, proportion of cases diagnosed, number completed treatment and rendered negative, are included in the assessment. Besides these, cost of the programme and expansion of the programme to the whole district, accuracy of the case index, operational achievements at individual centre/district, prevalence of initial drug resistance among clinic patients, should also be considered. Even such an elementary evaluation demands careful organization and clear procedures: staff must be allotted and trained for the purpose and equipment must be provided. The assessment must be objective and independent: it seems appropriate that the procedures would be undertaken, in each state, by staff from the State Tuberculosis Centre, Regional Offices under the Union Government could also be involved. The responsible centres must have portable, hand operated punching equipment and facilities for sputum culture. If tuberculosis in India is to be controlled by human intervention and health to be effectively promoted, independent assessment of programmes, feeding back into research so that problems will be solved and the solutions timely applied, is absolutely essential. As yet, both methodology and the organisation needed are embryonic and demand therefore particular attention and priority. Administrators and scientists alike face, in nurturing evaluation, an unusually difficult and promising challenge. Recognising and accepting a challenge is in itself an important development.

KEY WORDS: CONTROL PROGRAMME, EVALUATION, ASSESSMENT.

166
ASSESSMENT AND MONITORING OF NATIONAL TUBERCULOSIS PROGRAMME
SS Nair: Indian J TB 1971, 18, 131-34.

Assessment of a programme is the measurement of the extent to which its objectives have been fulfilled. This may be called assessment of efficacy. For this the objectives have to be defined in quantifiable terms i.e., the extent and period of time problem of tuberculosis will be reduced. This is yet to be done for the National Tuberculosis Programme (NTP). Assessment, of efficacy is difficult as the impact of Tuberculosis Programme is felt only after a fairly long period of time during which other socio-economic factors etc., also influence the problem. Any early assessment of problem reduction will only be a very costly attempt at proving the obvious and will possibly lead to frustration. Hence, a different methodology of assessment has to be adopted.

Assessment of Efficiency: Measurement of the extent to which the expectations for various activities under the programme are being fulfilled is referred to as assessment of efficiency. This seems to be a practicable solution to the problem of assessment of NTP. Realistic expectations for output and coverages under different activities can be set up on the basis of potentials on one hand and performance of programmes with reasonable efficiency on the other. Achievements of the programme could then be matched against these expectations. There is a need to define stages of programmes as different districts will have the programmes developed to different levels. Any overall assessment of such a heterogeneous programme situation may give a confusing picture. Advantages of this method are; i) number of districts which qualify to do from one stage to other will itself indicate the progress achieved; ii) after assessment attention can be concentrated on the corrective actions required. A detailed stage by stage assessment could be supplemented by monitoring i.e., a continuous watch on some key indices of the programme calculated from the periodic reports. This requires reasonably efficient reporting machinery. The key indices are: i) achievement of activities: Case-finding, treatment completion and BCG vaccinations against the expectations; ii) contribution from Peripheral Health Institutions; iii) No. of cases diagnosed against the prevalence of cases in the district.

Assessment should be objective enough to inspire confidence and its findings should be accepted or at least appreciated by the persons in-charge of the actual functioning of the programmes. For this, a proper climate for assessment should be created so that assessment is welcomed by programme organisers and corrective actions are taken soon after completion of assessment.

KEY WORDS: ASSESSMENT, MONITORING CONTROL PROGRAMME.

168
DETERMINATION OF APPROPRIATE INDEX AND TIME FOR ASSESSING THE EFFECTIVENESS OF TUBERCULOSIS CONTROL PROGRAMME
SS Nair: Indian J TB 1977, 24, 58-61

The present definition of the objectives of the National Tuberculosis Programme is too vague. A proper definition of the objectives, both longterm and intermediate, is needed. It should clearly state the index to be used for measurement of the problem and the expected values of this index at specific points of time. Another serious problem in assessment is to find out how much of the observed problem reduction is due to the impact of the programme and how much due to (or in spite of) the natural trend (downward or upward). Repeated surveys cannot provide this information and keeping of control groups is not feasible. Epidemetric models help in choosing the index for measuring the problem and fixing intermediate and long term objectives in terms of this index. They also help to take the natural trend into account, while assessing the programme.

Prevalence of infection is the least sensitive index. Prevalence of disease and incidence of infection may lead to over optimism. Incidence of disease is most suitable but difficult to get in developing countries. Hence, prevalence of infection or disease has to be chosen. Difficulties of the former are interference by BCG vaccination and non- specific sensitivity. The use of BCG induration to estimate prevalence of infection has some advantages and it is worthwhile to investigate further this possibility. Using epidemetric models, two methods of assessment of effectiveness are suggested. One to carry out prevalence surveys but need not be attempted unless programme efficiency has been quite high for at least 10 years. The other is the assessment of efficiency of the programme which can be easily carried out.

KEY WORDS: EPIDEMETRIC MODEL, CONTROL PROGRAMME, ASSESSMENT, EFFECTIVENESS, EFFICENCY.

169
A SIMPLE MODEL FOR PLANNING AND ASSESSMENT OF PROGRAMMES FOR TUBERCULOSIS CONTROL
SS Nair: Indian J Public Health 1977, 21, 111-31.

BCG vaccination (prevention) and Case-finding followed by treatment (cure) are two universally accepted methods for controlling tuberculosis. BCG trials in selected populations have provided some information on the protective value of BCG, generally over short periods of time (below 20 years) and mainly among younger populations. Efficacy of different drug regimens for treatment of tuberculosis are well established and a number of studies on the effectiveness of different types of treatment programmes on the patient population are available. However, the manner in which BCG and treatment affect the four epidemiological indices of prevalence & incidence of infection and prevalence & incidence of disease in the community, over a period of time, has not been reported in detail.

This paper describes a simple set of models which can be used to predict the trend from these indices under different types of TB programmes (including no programme) which can be depicted as a combination of 5 programme parameters. How these models can be used for planning and assessment of programmes have been demonstrated by some examples. The trend in the incidence of disease obtained from this model is similar to that reported by Waaler et al in 1974. Unlike earlier models, the present model starts with cases and the calculations involved are simple enough to be handled by calculators and computer facilities are not necessary.

KEY WORDS: MODEL, PLANNING, ASSESSMENT, CONTROL PROGRAMME.
 
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