Armstrong – Table of Contents

During World War II, effective louse control of the epidemics in the Mediterranean
Theatre was achieved by the use of the chemical insecticide DDT
(dichlorodiphenyltrichloroethane). During the outbreaks, the Armed Forces Medical
Services sprayed large numbers of the populations at risk by periodic liberal application
of DDT into the peoples’ clothing using hand-operated dusters. This procedure gradually
eradicated the incidence of infection along with whatever measures of personal hygiene
that could be accomplished.
Unfortunately, the lice became gradually resistant to DDT. DDT also tended to
accumulate in the tissues of living creatures resulting in adverse health effects. In 1962,
Rachel L. Carson, in her book “Silent Spring” (5), described the adverse effects on the
regional ecology of the environment caused by the widespread use of chemical
insecticides. This was one of the influences that led to the banning of DDT use in the
United States in 1972. Currently, other insecticides (malathion 1% and temafos [Abate]
2%) are effective for short-term use.
It is interesting to compare the methods described by Armstrong in controlling the
epidemic on the reservation where his group was dealing with an isolated, widely
scattered population in a predominantly semi-desert environment. Case finding was
challenging, and environmental and cultural factors had to be appreciated in order to
accomplish successful control.
During the latter months of 1920 and during the first half of 1921, 63 cases of
typhus with 27 deaths (@ 43% mortality) occurred on the San Juan Reservation. The
reservation comprising almost 6,000 (5,884) square miles lies in the 4-state corner area of
New Mexico, Arizona, Utah and Colorado. The area, as described, was primarily semi-