﻿IX, B, 1 



Heiser: Plague in the Philippines 



13 



On May 15, there was a second death from plague at 1226 

 Calle Juan Luna, the first cases having occurred on May 14. 



A review of the history of the plague outbreak in Manila 

 shows that the disinfecting and insecticidal measures taken at 

 each house must have been effective, because there is not a 

 single instance on record of a second case of plague having oc- 

 curred in any house after the incubation period of the disease 

 had expired. 



SEASONAL PREVALENCE 



The following table shows the prevalence of plague by months. 

 The seasonal prevalence of plague in many Oriental ports is of 

 the greatest epidemiological significance. In Hongkong, for in- 

 stance, the greatest number of cases for many years has gen- 

 erally occurred in May, and the smallest, in December. In Amoy, 

 which is several hundred kilometers farther north, the greatest 

 number of human cases occurs in June. The following table 

 indicates that the greatest number of cases occurs in the Phil- 

 ippines in October, but this can be considered more or less ac- 

 cidental, because the majority of those that occurred in October 

 were due to the explosive outbreak which was traced to the 

 Azcarraga railway station, and that can scarcely be ascribed to 

 seasonal reasons. There is also placed alongside the human cases 

 the incidence of rat plague, which shows that the greatest number 

 of plague rats was found in March. A study of these would 

 seem to show that if the often-quoted observation is true that 

 human cases should follow two months after rat plague has 

 occurred, the greatest number of human cases should have oc- 

 curred in Manila in May. The sanitary measures which were 

 so actively carried out against rats during March and April may 

 have prevented this. 



Table I. — Distribution by months of human and rat plague cases in Manila, 



Month and year. 



1912. 

 June 



July. 



Augnist - 



September 



October 



November 



December 



1913. 

 January 



Human 

 plague 

 cases. 



Rat 

 plag-ue I 



cases, i! 



2 















5 



1 



8 



2 



21 



1 



12 



1 



6 



3 



1 







Month and year. 



1913. 



February . - . 



March 



April 



May.- 



June 



July 



August 



September 

 October 



Human 



I plagne 

 cases. 



Rat 

 plague 

 cases. 



1 



13 

 3 

 7 

 8 

 

 

 3 

 



