18 



show that the residue of enteric is certainly not a persistent 

 one, and one need not hesitate to conclude that some of it, at 

 all events, is due to the existence of " carriers," insanitary 

 dwellings, slums, locally defective drainage, open middens, 

 ashpits, flies, etc. It is probable that far more stringent 

 sanitation in the overcrowded quarter of big towns will be 

 necessary to reduce the mortality to vanishing point, than has 

 been necessary to arrive at the present rate. The residue is 

 small, but the risk of any one person dying from enteric is still 

 appreciable, while the risk of illness is, of course, much greater; 

 it is no consolation to the typhoid patient to reflect that his 

 is only one of the dozen or two cases per million ! 



There is, of course, satisfactory evidence that typhoid 

 fever is conveyed by means of polluted shellfish, yet it is very 

 surprising to find that such satisfactory evidence is rather 

 exceptional. If it were not for the well-known cases of 

 epidemic illness following the two famous mayoral banquets 

 at Winchester and Southampton (the cases investigated by 

 Bulstrode) such evidence as is often adduced at the present 

 time would lose a great deal of its force. These two classic 

 investigations have, in fact, established a tradition which 

 subsequent work can hardly be said to have maintained. It 

 will be useful to quote some instances of the kind of evidence 

 that has been regarded as proving the connection of typhoid 

 fever and shellfish consumption : — 



(1) A ate steamed mussels on September 1st and fre- 



quently from then to November 29th. Then he 

 ate a raw mussel and said to his wife that it was 

 not good. He became ill on December 4th. His 

 blood reacted positively on December 27th. He 

 died on January 12th. 



(2) B ate cooked mussels on December 17th and he was 



ill seven days later. His blood gave a positive 

 reaction on December 29th. He died on January 3rd. 



