THE ANTI-MALARIA PROGRAM IN 
NORTH AMERICA 
By LOUIS L. WILLIAMS, Jr. 
UNITED STATES PUBLIC HEALTH SERVICE, WASHINGTON, D. C. 
Malaria is the disease of greatest eco¬ 
nomic importance in the southern portion 
of the United States and in the lowlands 
and river valleys of Mexico, Central Amer¬ 
ica, and the West Indies. The temperate 
climate of the northern United States with 
its short transmission season, makes this 
our only republic in which the natural 
processes of settlement could, and did, auto¬ 
matically remove malaria from a large por¬ 
tion of the richest section of the country. 
Drainage caused the major part of this 
recession; residual malaria left the area 
because of the screening of homes (Maps 1 
and 2). 
Although the growth of malaria control 
in the southern states increased rapidly 
between its inception in 1912 and the pres¬ 
ent time, the malarious territory did not 
decrease commensurately. The infected 
territory contracted, expanded and con¬ 
tracted, each time defining a smaller area 
until 1932, when it reached what is prob¬ 
ably its minimal endemic section. Since 
then, although less in intensity and more 
scattered in its endemic area, it is still 
found in The same portions of the same 
states as in 1912 (Maps 1912, 1932, and 
1934-35). 
In tropical America today, with its long 
MALARIOUS AREA OF THE UNITED STATES 
1882 
Map 1. Probable endemic area. 
MALARIOUS AREA OF THE UNITED STATES 
19 32 
MALARIOUS AREA OF THE UNITED STATES 
1912 
MALARIOUS AREA OF THE UNITED STATES 
_ 1934-5 
Map 2. Endemic area.' 
365 
Map 4. Endemic area. 
