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MAT.ARTA 
program a daily average of 211,000 men 
for 6.5 years have worked on anti-malaria 
drainage in an average of 250 counties. 
They have dug 33,655 miles of ditch, remov¬ 
ing 544,414 acres of anopheline breeding 
surface in the sixteen southeastern states. 
Today our defense program is creating 
many new camps in areas where malaria 
control is necessary. Two large projects 
to protect 4 camps and their maneuver area 
(costing nearly $1,000,000) have already 
been started. Several others of similar 
scope will be necessary as most of the 
larger training camps are located in the 
malarious southern states. Smaller proj¬ 
ects will have to be undertaken at many 
flying fields. As the range of the soldier, 
on pass, has increased from the 5 miles of 
the World War to 50 miles, malaria control 
will have to be affected in much greater 
areas. 
In Mexico, Central America, and the 
West Indies there has been no such stimu¬ 
lation either for research or for extension 
of control measures. Nevertheless in coop¬ 
eration with the Rockefeller Foundation 
and through fruit and oil companies, far- 
reaching malaria control projects have 
been completed and others are under way 
in 8 of the Caribbean countries of North 
America. 
The United States Public Health Service 
has worked out a Plan for State-Wide 
Malaria Control (Williams 1937b) which 
has four objectives: elimination of the 
major foci of infection in each county, pre¬ 
vention of man-made malaria, maintenance 
of existing and new control projects, and 
an educational campaign. 
The state boards of health press on con¬ 
tinuously toward these four objectives 
through a malaria control and investiga¬ 
tional unit within their own organization. 
This unit, in most of the southern states, 
is composed of a medical malariologist for 
epidemiological work, a sanitary engineer 
to plan for drainage, larvicides, and screen¬ 
ing, an entomologist to make anopheline 
surveys and one or more technicians to 
examine thick blood films. These last are 
attached to the state laboratory. 
The chief of the malarial unit chooses 
those counties considered most malarious 
for the first work. As early as possible in 
the autumn, thick film blood smears are 
taken from the 6 to 12-year age group of 
all school children in the rural areas and 
small villages. The slides go to the state 
laboratory for examination. The epidemi¬ 
ologist spots all positives by homes, thus 
revealing the foci of heaviest infection. 
The entomologist makes a complete anoph¬ 
eline survey of each focus. Based on this 
information, the sanitary engineer draws 
up a detailed plan of attack with an accu¬ 
rate estimate of cost. The chief of the unit 
determines whether the attack is to be by 
drainage, larvicide application, screening, 
or through treatment. This survey and 
plan are then laid before the authorities, to 
secure financing and operation of the con¬ 
trol project. 
To prevent man-made malaria, the ma¬ 
larial unit of each state makes contact with 
the builders of dams and insists on malaria 
control wherever waters are to be im¬ 
pounded. It cooperates with the highway 
department and the railroads traversing 
the state, to secure elimination of existing 
borrow pits and prevention of the forma¬ 
tion of new ones. It shows the companies 
engaged in lumbering the swamps, the 
malaria hazard they are creating and in¬ 
duces them to construct an outlet channel 
to all swamps where lumbering operations 
are in progress. 
As we have found that earth ditches are 
too expensive to maintain, units now urge 
that permanent lining be an integral part 
of anti-malaria drainage. We have learned 
from the work in Panama, Salvador, Nica¬ 
ragua, and from our own field experiments, 
that concrete inverts and bank sodding 
make a more permanent ditch requiring a 
minimum of maintenance. Ditch lining is 
now included in most of the anti-malaria 
drainage projects in the United States and 
of the other republics. 
The educational activities of the malarial 
unit include revision of the State Board of 
Health educational bulletins to keep them 
up to date, distribution of these bulletins to 
