83 



where possible, and oiled where it could not be drained. The results 

 look as if the focus of infection, at that particular point, had been 

 eradicated. In the case of the patient taken sick March 8th after our 

 disinfection, we went 42 days till the next case. Then an outbreak 

 occurred, April 2ist and 22nd. We again disinfected ; and went 15 

 days till the next cases, May 6th and 7th. We again disinfected, and 

 have gone 24 days without a case. I am more particularly impressed 

 by these figures, as we commenced our systematic destruction about 

 the middle of February. 



Formerly we paid no* particular attention to the mosquito, merely 

 disinfecting for yellow fever, as we do for other infectious diseases. 

 The only part of the process that killed the mosquito, was the 

 formaline used in one or two infected rooms. 



The amount of sanitary work done continues large ; but most of 

 our attention now is paid to the destruction of mosquitoes. The 

 suburbs, and all the small streams in the suburbs, have been pretty 

 thoroughly cleaned out ; and pools oiled and drained. 



The Mayor has issued an order prohibiting the keeping of stand- 

 ing water, anywhere within the city limits, unless made mosquito-proof. 

 This is being enforced ; and all standing water found not protected as 

 required is emptied, and the owner fined. 



We are employing about 75 men in this mosquito work, and have 

 gotten over the whole city during the last month ; and I expect to do 

 this every month during the summer ; at any. rate, as long as it seems 

 to have the present happy result. In this way, during the past month 

 we have used about 1,400 gallons of oil. 



June, 1901. 



The last death from yellow fever occurred on March i6th, three 

 and a half months ago. 



While we cannot say with any certainty that we will not have a 

 recurrence of this disease before the year is over, we can say pretty 

 positively that the excellent present conditions must be due to some- 

 thing that we are now doing which we have not done in past years. 



Commencing about the middle of February of this year, we based 

 our whole management of yellow fever upon the supposition that the 

 mosquito is the medium of its transmission from person to person, 



