On Preventive Inoculation. 



267 



reaching and most satisfactory results, was carried out, under Mr. 

 Cappel, late Collector of Dharwar, by Captain Leumann, LM.S , Dr. 

 (Miss) Corthorn, Dr. Hornabrook, Dr. Foy, Dr. Chenai, and others, in 

 three adjacent small towns of Hubli, Dharwar, and Gadag, where 

 80,000 people were inoculated. The latter was the most magnificent 

 piece of work done, from the point of view of practical application of 

 the method, and of the testing of its general efficiency. 



With the extension of the number of inoculated the exactitude and 

 precision of observation certainly suffer. A number of questions and 

 objections arise with regard to points of detail, which it is not always 

 possible to answer with certainty. Such wholesale observations are, 

 however, required to enable us to judge whether the application of the 

 method as a general measure answers to the expectations formed; 

 whereas the exact extent of the results is only to be gathered from 

 mathematically precise experiments, imitating the conditions of labora- 

 tory practice, such as were those which I have detailed above. 



The difference in. the mortality from plague in inoculated and unin- 

 oculated sections of communities was estimated to average over 80 per 

 cent., approaching often 90, as was the case in Undhera described 

 above. The lowest proportion ever observed in the experiments which 

 I made personally was 77*9 per cent. ; this was at Kirkee. 



Effect on the Case Mortality. 



A very accurate set of data were collected in almost all the larger 

 hospitals where inoculated plague cases were admitted, upon the fatality 

 of the disease in inoculated. These were to the effect that the case 

 mortality among them was some 50 per cent, lower than among 

 uninoculated plague cases. A number of documents on this point has 

 been collected by the Indian Plague Commission and will, I trust, 

 appear in their records. 



Minimum Duration of the Effect of the Plague Inoculation. 



As to the duration of the effect of the plague inoculation, the only 

 statement which can be made for the present is that it lasts at least for 

 the duration of one epidemic, which, on the average, extends over 

 four to six months of the year. 



The Government of India have recognised the inoculation certifi- 

 cates, entitling the holder to exemption from plague rules, as being 

 valid for a period of six months ; on the understanding that if accurate 

 data are forthcoming as to the effect lasting longer, the holders 

 will be permitted to renew their certificates for another period, without 

 being reinoculated. 



VOL. LXV. 



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