NAVMED P-5010-8 - Navy Medicine - U.S. Navy

8-42 CHAPTER 8. NAVY ENTOMOLOGY AND PEST CONTROL TECHNOLOGY 8-44
(c) When flea-borne diseases are
present, rat burrows should be dusted with an
insecticide prior to conducting rodent control
measures. This prevents fleas from leaving dead
or trapped rats and migrating to other animals or
human hosts in the area.
(3) Treatment of Infested Animals.
Because indoor flea infestations normally
originate from pets, a program for controlling
such infestations must include treatments of
these pets. Dogs and cats are best treated under
the care and direction of a veterinarian. Bedding
used by pets should be simultaneously treated.
8-43. Reduviid Bugs
a. Relation to Man. Reduviid or conenose
bugs of several genera, Panstrongylus,
Rhodnius, and Triatoma, are important to man as
vectors of the protozoan parasite, Trypanosoma
cruzi, which causes Chagas' disease or American
Trypanosomiasis. These insects occur in South
and Central America, Mexico, and in the Southwestern
United States. The infected insect bites
man, defecates during feeding or soon afterward,
and the infected feces is introduced into the bite
by scratching or rubbing. Infection can also take
place through contamination of the conjunctive,
mucous membranes, wounds, or scratches.
b. Biological Characteristics. Human
biting reduviid bugs are nocturnal, bloodsucking
insects that are about 13-19 mm (1/2-3/4
in) in length. The anterior half of the wing is
leathery and the posterior half membranous; the
head is cone-shaped with a proboscis divided
into three sections which are folded under,
between the front legs; and the abdomen is
flared out and upward to form a depression for
wings. The stages of the life cycle consist of an
egg, nymph, and adult. The nymphs are similar
to the adults except for being smaller and having
underdeveloped or partially developed wings.
The eggs are barrel-shaped and are deposited in
dusty corners of houses or in nests and burrows
of animal hosts. The young nymphs hatch from
the eggs to obtain blood meals from their hosts
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and shed their skins, developing into larger
nymphs in the process. This is repeated through
five nymphal stages to the adult stage. The
entire life cycle requires 1-2 years. The normal
hosts of these insects include rodents, bats,
armadillos, and sloths. To man, their bite is
usually painless and will not disturb a sleeping
person. There is usually no reaction to the bite,
but in some cases bitten individuals have experienced
symptoms of dizziness, nausea, and
intense itching on various parts of the body.
c. Control. Destruction of reduviid bugs
is difficult. Screening and otherwise making
dwellings insect proof can prevent their
invasions. Nests of wood rats and other host
animals should be eliminated in the general area
of dwellings, particularly under structures. For
chemical control, suspensions or emulsions
should be used as a residual treatment on the
interior walls and floors. Shelters or huts with
palm-thatched roofs should be avoided as
bivouac areas.
8-44. Rodents, Shipboard And Ashore
a. General. Rodents have associated with
man for ages. Several species are particularly
well suited for specialized conditions found both
aboard ship and ashore. The distribution of
rodents is worldwide; consequently, the problem
of control presents itself during operations in
any geographical location.
b. Relation to Man. Rodents such as rats,
mice, and ground squirrels may serve as reservoirs
for plague, endemic typhus, tularemia, and
other debilitating diseases. The problem of contamination
of supplies and direct property damage
by rodents may also be considered.
c. Important Species. The semi-wild
forms, which live in the jungles, forests, and
wastelands, have little or no contact with man
and are relatively unimportant in rodent control.
However, military operations and occupation
may change this situation. The most important
rodents from the medical and economical
viewpoint are:
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