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

8-56 CHAPTER 8. NAVY ENTOMOLOGY AND PEST CONTROL TECHNOLOGY 8-56
described for mosquito larvae. Larger flies, such
as domestic species, should be preserved in dry
pill boxes as detailed above for mosquito adults,
except that heavier cotton cushion layers will be
needed because of the greater weight of the
specimens involved.
(d) Ectoparasites. Particular
effort should be made to collect ectoparasites from
wild rodents suspected of being reservoirs of
disease (e.g., plague, tularemia, etc.). Because
fleas leave the host shortly after death, it is best to
capture the animal alive and sacrifice it with
chloroform in a closed container from which the
detached insects can be collected. Leave the
animal in the container at least 30 minutes after
death to ensure that the ectoparasites have also
been killed by the chloroform exposure. A finetooth
comb is used to comb fleas onto white paper.
Another technique for collecting fleas, as well as
some mites, is to place the dead host in a jar of
water containing a detergent and swirl the water
vigorously. After filtering the water with a filter
paper lined funnel, place the specimens in 70
percent ETOH as described for mosquito larvae.
Neither combing nor detergent baths will remove
stick-tight fleas or ticks. These must be picked off
with forceps during a thorough host examination.
When examining buildings for adult fleas, white
pants or coveralls will allow the adults to be seen
quite readily when they move onto the legs. They
can then be collected with a small alcohol
moistened brush. When examining animals for
ticks, care must be taken in their removal so that
the mouth-parts are not broken in the host's skin.
Ticks may be collected from likely host habitats
by walking through grassy or bushy areas and
removing them with forceps from the clothing or
from a piece of cloth used as a drag. The latter is
constructed by attaching a piece of white flannel
about 1 x 1.5 m (1 x 1.5 yds) by two corners to a
stick approxi-mately 1m (1 yd) long. A cord is
attached to both ends and the device is dragged
over grassy areas beside trails and other
potentially infested areas. The same device
without the cord can be brushed over shrubbery.
Collected ticks are placed in 70 percent ETOH.
The detergent technique described for fleas yields
some mites but chiggers are collected by scraping
the skin or, in the case of dead animals, portions of
infested skin may be cut off and preserved in
alcohol. Another method is to place a white or
black card on the ground. Mites are counted
and/or collected with a small, alcohol moistened
brush as they cross the card. Lice and bed bugs
may be collected from clothing and bedding with
forceps or combed from the hair with a fine-tooth
comb and placed in 70 percent ETOH.
(e) Miscellaneous Arthropods.
Insect larvae spiders, scorpions, centipedes
and millipedes may be preserved in vials of 70
percent ETOH. When corks or rubber stoppers are
used to close vials, it is best to seal them with
melted paraffin or parafilm to prevent fluid loss
through evaporation. If 5 percent glycerin is
added to the 70 percent ETOH, the collected
specimens will not shrivel, shrink, or dry if the
alcohol is accidentally lost. Larger, hard bodied
insects such as reduviid bugs, cockroaches and
beetles should normally be preserved dry in pill
boxes but they can also be placed in tubes or vials
of 70 percent ETOH.
(2) Pinned Specimens. If
possible, it is usually better to pin insects for
mailing because they are less likely to break if
properly packed. These specimens may be pinned
inside a closed vial with a cork bottom or in a
Schmitt, cigar or other sturdy box with a cork,
balsa wood, corrugated cardboard or composition
bottom. The pins should be securely anchored in
the substrate. Large specimens should be braced
with additional vertically placed pins to prevent
them from rotating and destroying adjacent
specimens. Insects with elongated abdomens
should be supported with crossed pins, thereby
preventing the abdomens from breaking off in the
event of rough handling during shipment. For
ease of extraction, the cardboard can be slotted or
a piece of adhesive tape can be attached to the
center for use as a handle. Fasten the lid securely
and pack the box or boxes in an outer stout carton
padded with a lining of excelsior, styrofoam or
similar packing at least 5cm (2 in) thick.
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9 Nov 2004