Bed Bug Management - Urban Insect Pests: Sustainable Management Strategies - page 15

conventional dry cleaning with perchloro-
ethylene has also been shown to kill all bed
bug stages (Naylor and Boase, 2010).

effects becomes more rapid (Pereira et al. ,
2009).
In bed bug control, a variety of techniques
may be used to heat individual items, rooms
or premises to levels where all stages of the
bugs are killed. On a small scale, a mobile
steamer (similar to a carpet cleaner) may be
used to direct a fl ow of steam into bed bug
harbourage areas. As with the use of freezing
carbon dioxide, care needs to be taken to
avoid dislodging the bugs before they have
received a lethal exposure to the hot steam.
Electrically heated containers, ranging
from ~1 to 5 m 3 , may be set up and used
within a building for treating smaller items,
whereas larger freight containers may be set
up outside a building for treating numbers
of beds and mattresses. These containers are
typically fi tted with sensors that measure
and record the actual temperatures reached
within the contents, to ensure that effective
temperatures are reached and maintained
throughout. Typically temperatures higher
than the lethal minimum are used in
practice to ensure rapid heat penetration
and kill (Kells and Goblirsch, 2011).
Alternatively, there are now a number of
systems that heat entire rooms or blocks of
rooms. The main electricity supply in
buildings cannot normally provide suffi -
cient power, so heat is typically provided
by a mobile diesel-powered external heater,
from which either hot liquid is piped to
heat-exchange units within the rooms
requiring heating, or hot air is ducted to the
required rooms. Again the temperature will
be monitored within the rooms, and
technicians may enter the rooms and use a
hand-held infrared thermometer to detect
cool-spots and adjust the heat movement to
compensate.

Vacuuming

Vacuum cleaners are sometimes used for
bed bug control. Careful and intensive
vacuuming will remove a proportion of the
more exposed bed bugs, although it is
unlikely to remove bugs concealed within
harbourages or remove many of their eggs,
which are cemented onto surfaces. It is
essential that appropriate steps are taken to
avoid the vacuum cleaner transferring bed
bugs between rooms and premises (Motoki,
2010).

Extreme cold

In general, the common bed bug is well
adapted to temperate conditions, and can
survive short exposure to temperatures a
few degrees below freezing. However,
exposure for >2 h to the temperatures
attained in a good domestic deep freezer
(-18°C) is lethal to bugs and their eggs
(Naylor and Boase, 2010). Items that may be
diffi cult to treat with other techniques, such
as topics, shoes or delicate clothing, should
be bagged and placed in a deep freeze for
several days, to ensure penetration of the
cold to the centre of the items. Freezing is
likely to be effective against both susceptible
and insecticide-resistant bed bug strains.
As an alternative to use of static freezers,
there is also a commercially available and
portable system that uses liquid carbon
dioxide to produce a jet of frozen gas with a
temperature of -70°C. The jet of gas is
directed to bed bug harbourages and,
providing the insects and their eggs are
directly exposed, they will be killed. The
advantage of this technique is its potentially
rapid action (Brown and Loughlin, 2012).

Pathogenic fungi

The use of pathogenic fungi to control
insect pests has been widely researched,
and is in regular use against a few pests
such as mosquitoes, locusts and aphids.
The effi cacy of Beauveria bassiana
(Deuteromycota: Hyphomycetes) has been
evaluated against bed bugs, by tarsal contact
with a surface deposit, with encouraging

Extreme heat

Bed bugs, like other insects, are adversely
affected by temperatures above about 40-
45 o C and, as temperatures rise above that
level, then the onset of damaging and lethal