ADDENDUM 



193 



bacilli from a virulent bovine culture. Some living tubercle 

 bacilli of bovine origin were found to have survived the treat- 

 ment given according to Method B, and Delepine adds " It may 

 be safely assumed that Method C, which yields a product giving 

 a higher total bacterial count than Method B, has even less effect 

 upon tubercle bacilli. The same bacilli resisted the process of 

 pasteurisation which forms part of Method A." 



" The tubercle bacilli which had survived pasteurisation in 

 Method A and drying by heat in Method B, were still capable 

 of producing progressive tuberculosis in guinea-pigs inoculated 

 subcutaneously with milk containing these bacilli but the course 

 of the disease produced by these bacilli was very much slower 

 than that of the disease produced in guinea-pigs inoculated with 

 the same amount of untreated tuberculous milk. The tuber- 

 culosis produced by the heated milk was latent or occult for some 

 four weeks. Young rabbits fed with milk containing these 

 modified bacilli did not contract tuberculosis." 



8. Bread. 



Bread is a food-stuff which is subjected to a certain amount 

 of bacterial contamination under the conditions of distribution 

 which prevail and it may be of interest to give some particulars 

 as to the extent to which it has been found to be bacterially 

 contaminated. 



From the Public Health point of view the only questions of 

 importance are : 



1. The extent to which bread and its constituents are 

 infected before baking and if any of the bacteria so taken up 

 survive the baking. 



2. The extent to which bread becomes infected with bacteria 

 on its surface and any evidence of the transfer in this way of 

 pathogenic bacteria. 



Apart from these points there are certain so-called diseases 

 of bread which render the bread sticky, slimy or sour. Such 

 conditions are bacterial in causation and different bacteria have 

 been isolated and described such as B. panis t B. liodermis and 



s. w. 13 



