148 MODE OF TRANSMISSION OF YELLOW FEVER 



often sought by tlie authority to compel owners or 

 occupiers of houses, building lots, outhouses, and 

 premises situate Avitliin 100 yards of tlie infected house 

 or premises, to destroy all mosquitos, larva?, pupa?, etc. 

 I am strongly of opinion that this is not sufficient. 

 The householder cannot, as a rule, carry out fumiga- 

 tion as described above. It can only be carried out 

 effectively by the proper staff, which should be that 

 of the medical officer of health. The result of the 

 householder carrying out fumigation is tliat the 

 majority of the mosquitos are not killed, that cases 

 of yellow fever occur in the so-called fumigated houses, 

 and that the method is brought into disrepute. I do 

 not think that the authorities always realise the 

 necessity of issuing stringent directions for the destruc- 

 tion of the yellow fever mosquito. The following 

 notice, for instance, is of little practical use : 



" Inside of houses care should be taken to destroy 

 mosquitos as much as possible, especially if there are 

 any cases of iever in the neighbourhood. This may 

 be done by burning either insect powder or tobacco 

 leaf freely in the room after closing tlie doors and 

 windows ; afterwards sweeping the ceilings, walls, and 

 floors, and destroying the sweepings (which will contain 

 dead and stunned mosquitos) by fire." 



This paragraph is of \ery little use to the house- 

 holder, and it certainly will not bring about the 

 effective destruction of mosquitos ; on the contrary, a 

 sense of false security may ensue. Those who have 



