c. Treatment. Treatment consists of chemotherapy, which is effective if started
before CNS involvement occurs. Natural immunity occurs in endemic areas, but there
is no known vaccine.
d. Prevention/Control. Prevention and control are based upon elimination of
the tsetse fly by wide clearings of brush around villages and along roads, streams, and
other routes of communication. All possible fly-resting sites should be sprayed with
Section VIII. FLEA-BORNE DISEASES
Fleas are small, wingless insects that feed voraciously on animals and
man. They are well adapted for jumping, and, though measuring only
a few millimeters in length, some can easily traverse a distance of 50
centimeters (about 20 inches) or more in one hop.
a. Disease Vectors. Several species are disease vectors, but the one of
primary military importance is Xenopsyl/a cheopis, Oriental rat flea, which is the
principal vector for plague and endemic (murine) typhus. Both the male and the female
of this species are bloodsuckers. They tend to prefer the rat host but will readily leave a
feverish or dead rat and seek a new host, attacking man readily.
b. The 4-Stage Life Cycle of the Flea. Fleas go through a 4-stage life cycle
(Figure 5-11) that may require from a few days to over 200 to complete.
After fertilization and a blood meal, the female lays eggs.
The eggs develop into larvae which feed on flea excreta, debris found in
the burrow, nest, or shelter of the host.
The larvae then spin a cocoon, pupate, and emerge as adult fleas.