232 MECHANISM OF INFECTION AND IMMUNITY 



limited on account of infirmity. The reason for this is too obvious to 

 need statement, and it follows that more men than women and more 

 adults than children have typhoid fever. Moreover, the case mortality 

 is greater among the strong, because death in this class of infectious 

 diseases is often due to the rapidity with which the invading organism 

 is broken up by the secretions of the body cells and the protein poison 

 made effective. From this I have concluded that contagion, like war, 

 destroys the very flower of the race. This view is sustained by the 

 historians of the pestilences of former times. 



Thucydides, in his description of the plague at Athens, says: 

 "Moreover, no constitution, whether in respect of strength or weakness, 

 was found able to cope with it ; nay, it swept away all alike, even those 

 attended to with the most careful management." Procopius, in his 

 account of the Justinian epidemic, states that youth was the most 

 perilous season, and females were less susceptible than males. Cogan, 

 in describing an outbreak of typhus at Oxford in 1577, writes: "The 

 same kind of ague raged in a manner over all England and took away 

 very many of the strongest sort, and in their lustiest age, and for the 

 most part, men, and not women and children, culling them out here 

 and there, even as you would choose the best sheep of a flock." In 

 his account of the plague of 1665 in London, Boghurst makes the 

 following statement: 



Of all the common hackney prostitutes of Luteners-lane, dog-yard, cross- 

 lane, Baldwins-gardens, Hatton-gardens and other places, the common criers 

 of oranges, oysters, fruits, etc., all the impudent drunken, drubbing bayles and 

 fellows and many others of the rouge route, there is but few missing verify- 

 ing the testimony of Diemerbroech that the plague left the rotten bodies and 

 took the sound. 



Like testimony comes from an account of the plague at Moscow: 

 "Drunkards and persons of feeble temperament were less subject to 

 attack." Davidson observed that typhus fever was more frequent 

 among the robust than the weak. He states that out of 429 cases, the 

 spare and unhealthy taken together made only about 17 per cent. He 

 adds that the death-rate among the poor was one in twenty-three, while 

 among the well to do, it was one in four. The greater mortality of 

 typhus among the higher classes has been noted by Barber and Cheyne 

 and by Braken. Hurty, nearly a century ago, wrote : "A fever which 



