YELLOW FEVER 261 



the following circular, which was submitted for my 

 approval by the chief surgeon, Department of Cuba, 

 and was published by the commanding general of 

 that department. 



" CIRCULAR ) " HEADQUARTERS DEPARTMENT OF CUBA, 

 " No. 5. ) " Havana, April .27, 1901. 



*' Upon the recommendation of the chief surgeon of the depart- 

 ment, the following instructions are published and will be strictly 

 enforced at all military posts in this department: 



"The recent experiments made in Havana by the Medical 

 Department of the Army having proved that yellow fever, like 

 malarial fever, is conveyed chiefly, and probably exclusively, by 

 the bite of infected mosquitoes, important changes in the meas- 

 ures used for the prevention and treatment of this disease have 

 become necessary. 



" i. In order to prevent the breeding of mosquitoes and to pro- 

 tect officers and men against their bites, the provisions of General 

 Orders No. 6, Department of Cuba, December 21, 1900, shall be 

 carefully carried out, especially during the summer and fall. 



" 2. So far as yellow fever is concerned, infection of a room or 

 building simply means that it contains infected mosquitoes, that 

 is, mosquitoes which have fed on yellow-fever patients. Disin- 

 fection, therefore, means the employment of measures aimed at 

 the destruction of these mosquitoes. The most effective of these 

 measures is fumigation, with either sulphur, formaldehyd, or 

 insect powder. The fumes of sulphur are the quickest and most 

 effective insecticide but are otherwise objectionable. Formalde- 

 hyd gas is quite effective if the infected rooms are kept closed 

 and sealed for two or three hours. The smoke of insect powder 

 has also been proved very useful; it readily stupefies mosquitoes, 

 which drop to the floor and can then be easily destroyed. 



** The washing of walls, floors, ceilings, and furniture with dis- 

 infectants is unnecessary. 



" 3. As it has been demonstrated that yellow fever cannot be 



