FLEA CARRIERS OF THE PLAGUE 



Tiir. i'i.A(;rK c;khm i\ man is idkmk ai. with thai" in iiik rat and 



KI.KAS MAY ( AKUV TlIK (iKK.M TO MAX 



Ihl Fraiil: E. Liifz 



S( 1 1'",\( v. was late in (lisf()\('i-in<i' and llic world in acccjit iii,u I lie knowl- 

 edge that insects may 1k' conunon carriers of disease. In fact it is 

 not so \^'\■y many years since science isolated the minute germs 

 themseKt's for identification in such cases as typhoid, malaria, yellow fever 

 ami plague. To-day fiies and mosquitoes stand convicted the world over 

 as carriers of disease germs and the warfare against them is well on. In 

 this case there are three factors concerned in the battle and man conquers 

 the germ by exterminating the insect. 



Fleas as disease carriers have been conspicuously before the world of 

 late; they also stand convicted, but the question concerns the interrelation- 

 ship of four: man, the flea as carrier, the rat or other animal on which the 

 flea is parasitic and the disease germ. Again warfare is against the insect 

 but to be successful it must be directed with full force againet the rat, its 

 host. Would that in all instances the whole trio — rat, flea and germ — 



Head of rat 

 flea. Many 

 plague germs 

 may be carried 

 on the mouth 

 part-s of a fiea 



and 5000 or 

 more In the 

 stomach where 

 t hey will live 

 or 15 to 20 

 (lays 



Photomicrograph ' 



' Flea illustrations from Doane's Insects and Disease by courtesy of Henry Holt and 

 Company. Other cuts by courtesy of McClure's and Country Life in America 



95 



