HISTORICAL INTRODUCTION TO MALARIA 
7 
with such a scope are exceedingly costly. 
While not decrying such extensive pro¬ 
grams where they can be afforded, their 
example nevertheless has. doubtless re¬ 
tarded the extension of simpler programs 
with a definite sanitary objective. Atten¬ 
tion to the role of different species of 
anophelines in malarial transmission has 
shown that great economies can be effected 
by limiting a project to the actual trans¬ 
mitting species, a practice known as “spe¬ 
cies sanitation, ’ ’ exemplified by the success¬ 
ful results in the Canal Zone which were 
obtained by directing efforts to the control 
of A. albimanus. 
Under practicable circumstances the 
routine distribution of substances toxic 
for mosquito larvae is of great value in the 
control of mosquitoes. Prior to the recog¬ 
nition of their disease conveying powers, 
mosquitoes attracted so little attention 
from scientists and the laity that a contri¬ 
bution which appeared in the American 
Daily Advertiser of Philadelphia, on Au¬ 
gust 29, 1793, when an epidemic of yellow 
fever was raging in that city, is remark¬ 
able. The anonymous contributor urged 
the householders to pour a gill of oil on the 
water in rain barrels and to add more to 
cisterns in order to kill the mosquitoes 
therein (Middleton 1928). It is certain 
that any oil which may have been used at 
that date was not petroleum, but more 
likely whale oil. In 1892 Howard was one 
of the earliest to employ a petroleum oil 
(kerosene) for the destruction of mosquito 
larvae (Howard 1900), and for many years 
thereafter various petroleum derivatives 
were the most commonly employed larvi- 
cides. Since stomach poisons are so widely 
used in the control of insect pests, it is 
rather remarkable that their adaptation to 
mosquito control came at a comparatively 
late date. The possibilities of the best 
known insecticide of this type, Paris green, 
were ascertained by Barber and Hayne in 
1921, subsequent to which its use as a larvi- 
cide has become widespread. 
The application of metallic wire cloth to 
doors and windows of dwellings in order to 
exclude mosquitoes and other noxious in¬ 
sects is a practice that has had its widest 
development in the United States. Just 
when it was first introduced is uncertain, 
although some was manufactured as early 
as 1865. The amount now annually manu¬ 
factured for domestic consumption and ex¬ 
port is enormous, in 1927 exceeding 500 
million square feet. 
The Need for Intensification of 
Research on Malaria 
In another connection the writer (1939) 
has briefly reviewed certain aspects of the 
present status of the malarial problem. 
While recognizing that present available 
knowledge is not being applied in some 
areas with adequate resources for the con¬ 
trol of malaria, nevertheless there are 
many regions in the world where any at¬ 
tempt to control this disease based on the 
application of available measures is beyond 
local resources. Malaria will likely con¬ 
tinue to be endemic in such regions until 
cheaper control methods are devised. The 
hope of cheaper methods depends upon 
the acquirement of new viewpoints to the 
problem, the attainment of which necessi¬ 
tates an extension of our knowledge. Prob¬ 
ably no better guide to the needs and op¬ 
portunities for research in the field of 
malaria can be secured than through an 
inventory of existing knowledge which this 
symposium is designed to supply. 
