172 THOMPSON YATES LABORATORIES REPORT 
they do not appreciate the danger of being bitten, or from mere carelessness, are 
unwilling to take any trouble to avoid the bites of anopheles. It is, therefore, usual 
to see mosquito nets used in such a way that they afford but slight protection ; 
whereas by the use, with scrupulous and unremitting attention, of a mosquito net 
a careful man may remain years in a malarial district without contracting malaria. 
It is also highly improbable that many men in Africa would so effectually exclude 
anopheles from a mosquito-proof house as the investigators on the Roman Campagna 
did. Indeed, it is highly probable that mosquito-proof houses would be as useless 
in the hands of most men in the tropics as mosquito nets are at present. Methods 
of protection from bites of anopheles are of great efficacy to those who are content to 
undergo some discomfort to avoid malaria, but of very little use to the average man 
who as yet protects himself at best only half-heartedly. 
Mosquito Nets. As a means of protection the proper use of a mosquito net 
stands pre-eminently alone. Anopheles in most places do not bite by day, and as a 
rule are not very bold, so that they do not bite freely until the lights are out. By 
the careful use of a net the bites of anopheles may be almost done away with. 
Clothing. A great deal of protection is afforded by the habitual use of certain 
precautions of dress. It is rare whilst a light is in the room for the face and hands 
to be bitten by anopheles. The parts usually bitten whilst one is still outside the 
net are the ankles, which are usually freely exposed, covered only by a single thickness 
of sock. By the use of double socks, mosquito boots, or puttees the ankles may be 
perfectly protected. 
Mosquito-Proof Houses. As mentioned above mosquito-proof houses have been 
shewn to be feasible in Italy. It is, however, unlikely that such a means of protec- 
tion will be largely used in the tropics. The climate in Italy and Africa are entirely 
different. In houses such as Drs. Sambon and Lowe occupied, life in the tropics 
would be most unpleasant. With the most perfect ventilation, with doors and 
windows thrown open, it is often so excessively hot at night that sleep is difficult. 
Most Europeans occupy rather large and roomy houses and spend much of their 
spare time on the verandah. Protection of this kind we shall see also later is by no 
means the most promising method of preventing malaria among Europeans in Africa. 
Repellant Bodies. So far no repellant body of any effectiveness has been 
discovered. 
III. THE ELIMINATION FROM A COMMUNITY OF THE 
SOURCE OF INFECTION IN MAN 
Two most important methods have the above result as their aim. They are : 
i The method employed with success by Professor Koch in New Guinea, 
■viz., to search out all cases of malaria (the concealed ones in particular), and to 
render them harmless by curing them with quinine. 
