198 TROBLEMS AND PRINCIPLES OF MALARIA PREVENTION. 



space without unduly weakening the fabric, the air space will not 

 he reduced more than about 35 per cent, and that does not 

 matter much even in a tropical climate, provided the ventilation 

 spaces are properly designated and the gauze is kept reasonably 

 clean by brushing. 



The window screens must be fixed, not of the sliding variety. 

 Experience has shown that sliding screens are seldom kept shut 

 and in a mosquito-proof condition. 



It is advisable to screen the verandahs, and not the windows 

 only. Verandah screens do not deteriorate as rapidly as window 

 screens, and are thus, in the long run, cheaper. Screenqd venm- 

 dahs also insure greater protection to the household by providing 

 it with a mosquito-proof lounging space for the hot season, and 

 the ventilation of the house is not nearly ?^o much interfered with 

 as when windows only are screened. 



The house must be carefully examined for openings in the 

 floor, ceiling, ventilators, around chimneys, etc., and all these 

 must be made mosquito-proof. In one-storey houses with 

 straight, short chimneys from fire-places, these should be made 

 mosquito proof by inserting well-fitting panels when the fire- 

 places art not in use. 



All outer doors must be made to open outwards, must have 

 efficient self-closing devices, and must make a mosquito-proof 

 joint with the frame. 



wScreened vestibules, or what are generally called " double 

 doors," are necessary only in localities where mosquitos are very 

 al)undant. 



Mosquito catching, by means of suitable trajis or with the 

 aid of slappers, chloroform tubes, and similar devices, is a very 

 useful measure if systematically carried out. It should be done 

 twice daily — early in the morning and just after sunset. 



(4) The Protection of the Individual by Medication. — 

 Quinine, when taken regularly in proper doses, is a fairlv efi'ec- 

 tive measure of prophylaxis. It has been applied with success 

 in the malarious part of Italy. Its exact value in eradicating 

 malaria in a fairly large territory is still a debatable matter, but 

 it is unquestionably valuable to the hunter, prospector, troops 

 •campaigning in malarious districts — in other w<irds. to persons 

 compelled to spend some time in a malarious locality. Quinine 

 should be augmented by the use of mosquito nets, screened tents 

 or houses, and a systematic search and destruction of niosf|uitos 

 Avithin the tents or other dwellings. 



(5) A Couihination of Several or all the Methods Enumer- 

 ated. — In extending the work of malaria prevention over a con- 

 siderable area, it is usually found advisable not to relv entirely 

 on one line of effort. The exact combination used depends, of 

 course, on local conditions. Whatever plan is adopted, it is 

 always essential in an anti-malaria campaign covering a large 

 population to secure the co-operation of the public by an intelli- 

 gent, enthusiastic, and sustained campaign of education. Pnl)lic 



