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at the pupal stage in untreated sentinel
oviposition sites located 2 metres from the
auto-dissemination stations.
This approach takes advantage of the
natural skip oviposition behaviour of
Aedes
mosquitoes, whereby they will visit
many water bodies and lay a few eggs in
each. Development work is proceeding to
optimize the design of the auto-
dissemination device; for example, Rutgers
University has received a grant on this topic
from the US Armed Forces Pest Management
Board Deployed War-Fighter Protection
(DWFP) Programme in 2012.
Recently Knols (2013) announced a
novel mosquito trap, the 'In2Trap'. This
includes attractant, pyriproxyfen and an
entomopathogen. EU Seventh Framework
Programme (SP7) Funding has been
obtained to develop this approach to a stage
ready for industrial production by 2015.
of the mosquito from some areas (Kay
et al.
,
2002), based on extensive community
involvement, removal of temporary water
bodies and allowing the copepods to remain
in water storage containers. Marten (1990)
demonstrated that
Mesocyclops albidus
could control
Ae. albopictus
in stacks of
discarded tyres near New Orleans very
effectively.
Copepods can be cultured rapidly (e.g.
50 copepods in a 150-litre container can
multiply to 10,000 in 3 weeks). Storage is
possible at low temperature or on damp
sponge substrate and they can be applied
through a spray nozzle (Marten and Reid,
2007). Field trials in temporary pools,
marshes and rice fi elds have demonstrated
that the introduction of the appropriate
copepod species at the right time can
eliminate
Anopheles
or fl oodwater
Aedes
larvae. Copepods cannot normally eliminate
Culex
by themselves but their use can
support other management methods (Marten
and Reid, 2007).
Nematodes
The mermithid nematode
Romanomermis
culicivorax
kills mosquito larvae. It has
been successfully mass reared, and it can be
applied through conventional spray equip-
ment and has the potential for establishment
in the environment leading to long-term
control. A product was commercialized in
the 1970s in the USA under the name
'Skeeter Doom' and the economics of use
appeared relatively favourable with nema-
todes costing as little as US$3.95/ha for
aerial application in Florida in 1977 (Giblin,
1987). In addition Rojas
et al.
(1987)
demonstrated that the nematode was able to
control
An. albimanus
successfully in El
Valle, Colombia, which led to long-term
suppression of mosquito abundance and a
rapid and progressive reduction in preva-
lence of malaria.
Densovirus
Mosquito densoviruses (MDVs) are specifi c
to mosquitoes, replicate in the larval cell
nuclei and kill them. Buchatsky
et al.
(1997)
demonstrated that the
Aedes
densovirus
(AeDNV) was pathogenic to larvae of all
Aedes
and
Culex
species tested. Infected
larvae that survive to become adult mos-
quitoes have a shortened lifespan and many
do not survive longer than the extrinsic
incubation period for arboviruses. Infected
females can transmit MDV vertically by
laying infected eggs in new oviposition
sites, thereby auto-disseminating the virus.
In cage experiments Suchman
et al.
(2005) demonstrated that the AeDNV virus
can accumulate and persist in
Ae. aegypti
larval rearing sites to concentrations that
affect the lifespan and vectorial capacity of
the mosquitoes and that it can be spread to
new larval rearing sites. In other large cage
experiments Wise de Valdez
et al.
(2010)
also found auto-dissemination occurred but
the AeDNV levels reached were insuffi cient
to reduce egg densities.
Copepods
Predatory
Mesocyclops
copepods kill
Aedes
larvae and have been used in successful,
large-scale control programmes for
Ae.
aegypti
in Vietnam, involving elimination
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