﻿IX, B, 1 Heiser: Plague in the Philippines 23 



the house in which the plague infection had occurred, and this 

 was apparently successful in preventing extensive spread of 

 plague among rats. All new buildings now erected in Manila 

 or extensive repairs in old ones must be made rat proof. A 

 special set of building regulations for this purpose has been 

 promulgated. Not much stress was laid upon disinfection. The 

 principal reliance was had upon using petroleum as an insecticide. 

 The rat-catching measures were supplemented by a general clean- 

 ing up in a suspected zone of all premises by a force of several 

 hundred laborers, which resulted in discovering the hiding places 

 of many rats and the destruction of rat nests. Particular atten- 

 tion was given to finding rat nests and destroying them, with 

 the hope that in this way the transfer of plague-infected fleas 

 to healthy rats would be best obviated. Dogs were extensively 

 employed in these cleaning-up measures, and they caught many 

 rats during the process. Manila's experience indicates that 

 plague is not a filth disease. The spread of plague to the prov- 

 inces was prevented by the inspection of all cargo that was sent 

 out in order to be certain that it harbored no rats. From careful 

 statistics kept with regard to the effectiveness of various forms 

 of rat traps it was ascertained that the spring or snap is ten 

 times as effective as the wire-cage trap and that the wire-cage 

 trap is more effective than one portion of poison. 



