14^ :modp: of tuansmission of yellow fever 



2. General screening of the reservoirs bij the use 

 of an I sol (it ion Hospital. 



This is a most userul measure because amongst the 

 poor or careless it is very diflicult to maintain efficient 

 control Avithout the employment of much elaborate 

 machinery and a considerable expenditiu'e of money. .. 



3. Isolation hij screening tJie Reservoir. 



A great deal can be done in the direction of pre- 

 venting the spread of the disease by screening the 

 patient, and so preventing the mosquitos from becoming 

 infected and spreading the disease. 



Both with regard to the isolation of the patient and 

 the application of fumigation there is a great want of 

 precision. It is useless for any one to apply these two 

 cardinal preventive measures unless they understand 

 the role of the mosquito in the dissemination of the 

 disease. The infected mosquitos have to be destroyed 

 both in the house of the patient and often in the 

 adjoining blocks, and the patient must be so placed 

 that no mosquitos can gain access to him. Those who 

 are familiar with the habits of mosquitos know that it 

 is not an easy task to bring about their thorough 

 destruction in living-houses, and that fumigation must 

 be applied with absolute thoroughness to all parts of 

 the house, closets, and outhouses ; and that to do this 

 the house, closets, and outliouses must be so completely 

 sealed that a mosquito cannot get away through any 

 chink. ^Vgain, those familiar with mosquitos know 

 that it is very difficult to keep them out of screened 

 rooms, unless tiie screening is well done and the doors 

 are of the proper kind. It is only by the rigid applica- 



