


pr ll on aid) abel 
YELLOW FEVER 
Cast-out pots and cans should 
be removed to prevent the accu- 
mulation of rain-water, while for 
rain-barrels, screening is essential. 
2. Destruction of wigglers — 
‘They may be suffocated by 
oiling the surface of the water in 
which they live, or killed by 
poisoning. 
Their natural enemies, es- 
pecially small fishes, should be 
encouraged. 
3. Destruction of adult mosquitoes by 
fumigating — 
Cellars in which they hiber- 
nate and houses in which cases of 
malaria have occurred should re- 
ceive special attention. 
4. Screening to keep mosquitoes away 
from malaria patients from whom 
infection may be derived and away 
from healthy persons whom they 
might infect. 
When the use of screens is imprac- 
ticable it is often possible to drive mos- 
quitoes away by the use of repellants. 
The phenomenal success of the 
battle against mosquito-borne disease is 
discussed in the section on yellow fever. 
YELLOW FEVER 
Yellow fever is atropical disease, the 
cause of which was shrouded in mystery 
until the beginning of this century, when 
its connection with the mosquito was 
established. 
A typical vacant lot breeding-place is 
reproduced in the bottom of WALL 
CASE 6 and above is a properly 
screened rain-barrel. 
Samples of oil are arranged on the 
middle shelf of WALL CASE 6, and 
a jar just above shows the condition 
produced by oiling. At the lower left 
corner of the case is a barrel used for 
applying oil to running water. ‘The 
picture behind it is of an oiling squad 
in New Jersey. 
A sample of the poison used in Panama 
is shown. 
The most important insect enemies of 
the mosquito are displayed in WALL 
CASE 8, and in WALL CASE 6 is 
a group of fishes devouring their prey. 
In WALL CASE 7 1s shown a 
screened hospital compartment, and 
a portable net for protection against 
mosquitoes. 
Samples of repellants are shown in 
WALL CASE 6. 
CHARTS 16 and 17 show the place 
where the discovery was made, and 
the heroes who accomplished it. 
