Agriculture Reference
In-Depth Information
from one species to another does not
involve GM technology. However, once
female mosquitoes are released that
contain a new strain of
Wolbachia
, the
strain cannot be recalled and so the
possible outcomes of selection pressures
on the pathogen, the
Wolbachia
and the
mosquito need to be considered. The
fi eld substitution of a mosquito species
able to transmit disease with one that is
not able to do so is yet to be demon-
strated.
• Practical deployment of other genetic
systems, such as RNAi and HEGs, may
be subject to considerable regulatory
barriers because they involve the persist-
ence of genetic modifi cations in the
environment.
• Ivermectin could contribute to reducing
transmission of malaria but in order to
have a major impact it would need to be
administered frequently to the entire
human population in the area concerned.
the urban vector
An. stephensi,
provided
the stability of the system in fi eld use is
proven.
The costs of each of the emerging
technologies will also be critical to their
practical success. It may, however, be more
cost-effective in the long term to replace an
established, low-cost technology with one
with higher cost and greater effectiveness.
In particular where technologies are well
suited to elimination of a vector-borne
disease a high cost can be acceptable during
the elimination phase. This would favour
SIT, RIDL,
Wolbachia,
other genetic
approaches and potentially ivermectin.
No single technology provides a magic
bullet for mosquito control and over-use of
a single approach will lead to the
development of resistance. The selection of
mosquito management technologies should
depend on the local circumstances and a
combination of approaches will normally
be the most effective and sustainable
solution in an Integrated Mosquito Manage-
ment (IMM) Plan. This includes integration
with environmental management and with
other urban services and health programmes.
It is also essential to involve local com-
munities and to keep them informed and
engaged in order to ensure acceptance of the
interventions and to maximize their
effectiveness.
Considerable public and private funding
has supported the development of the
emerging technologies, including grants
from the Bill and Melinda Gates Foundation.
It is clear that several of the technologies
show promise and, in order for them to be
incorporated in regular mosquito manage-
ment programmes, the bodies responsible
for evaluation, approval and adoption of
new technologies at national and inter-
national level need to open up to new ways
of working and to facilitate trials, regulatory
review and deployment.
From the above analysis it appears that
only a few of the emerging technologies
have strong prospects of widespread adop-
tion in the urban environment. The tech-
nologies with best prospects are
impregnated fabrics, RIDL, Spatial Decision
Support Systems and potentially sugar
baits. Products to improve water quality are
likely to have potential for
Culex
manage-
ment once their effectiveness has been
proven and copepods are effective against
Aedes
in specifi c situations. Polystyrene
balls have a niche application for
Culex
in
open latrines. The potential of adult traps
and dissemination systems to reduce
disease transmission remains an open
question to be answered through further
research. There may be an opportunity for
use of certain
Wolbachia
strains to reduce
or eliminate transmission of disease by
some mosquito species, such as malaria by
Search WWH ::
Custom Search