230 



To be in conformity with these agreements regarding the de- 

 struction of rats, quarantine authorities may demand the fumigation 

 of infected and suspected ships; suspected ships within the meaning 

 of the treaties being those on board of which there have been a case 

 or cases of plague at the time of departure or during the voyage, 

 but no new case within seven days. In the case of indemne ships, 

 on the other hand, without demanding it as a general rule, the sanitary 

 authorities may subject them to fumigation to kill rats. When upon 

 such ships rats have been recognized as pest stricken, as a result 

 of bacteriological examination, or when a marked mortality has been 

 established among these rodents, fumigation is prescribed. 



While the classification of ships and the limitations placed on 

 quarantine procedures in relation thereto, as contained in existing 

 international sanitary agreements, is more apparent than real, there 

 appears to be a lack of exactness with respect to the destruction of 

 rats necessary for the prevention of the importation of plague from 

 one country to another. 



Since the adoption of the international sanitary agreement of 

 Paris in 1903, some of the unproven convictions of that time regarding 

 the role of rats and fleas in the transmission of plague have been proven 

 to be positive facts. Many epidemiological observations and exact 

 scientific experiments have demonstrated particularly the importance 

 of the rat in the propagation of plague and the role of the flea as the 

 carrier of infection from rat to rat and from rats to man. 



At the same time there has been a growing conviction that other 

 agencies, such as passengers, baggage, and merchandise play a very 

 minor role in the dissemination of plague. It is of interest, there- 

 fore, to review the efforts being made at the more important sea- 

 ports to exterminate rats, as well as the methods being employed 

 to that end. 



INQUIRY INTO THE CRUSADE AGAINST RATS THROUGHOUT THE 



WORLD. 



The first law in modern times aiming at the destruction of rats 

 appears to have been enacted in Barbados in 1745. a According 

 to Boelter this act was incorporated into a new act which was 

 passed in 1748. The same author states that the next legislative 

 body to enact a law against rats was in Antigua in 1880. In the 

 same article he refers to the rat ordinance of Hongkong, adopted 

 in 1902. 



Private measures against rats have undoubtedly been practiced 

 from time immemorial. The action of Denmark, however, in passing 

 a law for the systematic destruction of rats and providing the organ- 



a W. R. Boelter, "On Rat Laws, " Journal of Incorporated Society for the Destruc- 

 tion of Vermin, October, 1908. 



