416 



The Philippine Journal of Science 



1913 



transmission of plague. Although many investigators have been 

 successful in demonstrating the presence of Bacillus pestis in the 

 digestive system of bloodsucking insects, it was not until the 

 experiments of Gauthier and Raybaud that the actual transmis- 

 sion of plague infection by fleas was convincingly proved. Ever 

 since the exhaustive and conclusive experiments, which were 

 carried out both under natural and artificial conditions by the 

 British Plague Commission, and the work of Verbijtski, which 

 antedates the British Commission, were presented, there has been 

 no doubt that the transmission of plague by bloodsucking insects 

 particularly by the fleas is one, although not the only, mode 

 of spreading this disease. It is obvious, as Herzog correctly 

 remarks, that the factors which are responsible for the spreading 

 of plague must be considered individually in each epidemic 

 and in various parts of the world as well. There is no doubt 

 that the importance of any insect in the transmission of plague 

 depends on its habits as well as on those of the host, be it either 

 animal or man. 



Table III. — Insects found to contain Bacillus pestis. 



Author. 



Yersin 



Nuttal 



Do 



Do 



Hankln 



Do 



Ogata 



Simond 



Tindswell, 1900 



Tindswell, 1903 



Kolle 



Gauthier and Raybaud . 

 Li8ton ._ 



Zirolia 



British Commission. 

 Verbijtski 



Insect. 



Flies 



do 



Bedbugs 



Flea 



Ant's faeces. 



Bedbugs 



Flea 



do 



do 



do 



do 



do 



do 



La Bonadiere and 



Xanthopulides. 

 Herzog 



do 



do 



Flea and bedbug.. 

 Fly 



Pedieulus capitis. 



Source of infection. 



Experimental 

 transmission. 



-I 



Laboratory infection 



Experimental infection ... 



do Negative by bite. 



.do. 



Negative. 



Fed on plague material 



Plague hospital 



Plague rats -I 



Plague rats, experimental Positive. 



Plague rats.-. \ Negative. 



do i Do. 



Experimental infection I Do. 



do --- I Positive. 



Epidemic among pigs; harbored i Do. 



fleas; dead rats found. ' 



Retained Bacillus pestis, 7-8 days. \ 



Repeated experiments 



Experimental infection 



Dead body of a plague case . 



Do. 

 Do. 



During the recent outbreak of plague in Manila, several 

 samples of bedbugs from the beds of the plague patients and 

 dog fleas from a plague-infected house were collected and ex- 

 amined, but with negative result. 



In spite of the fact that it adds nothing new to the question 



