• FluTrackers.com Inc. does not provide medical advice. Information on this web site is collected from various internet resources, and the FluTrackers board of directors makes no warranty to the safety, efficacy, correctness or completeness of the information posted on this site by any author or poster. The information collated here is for instructional and/or discussion purposes only and is NOT intended to diagnose or treat any disease, illness, or other medical condition. Every individual reader or poster should seek advice from their personal physician/healthcare practitioner before considering or using any interventions that are discussed on this website. By continuing to access this website you agree to consult your personal physican before using any interventions posted on this website, and you agree to hold harmless FluTrackers.com Inc., the board of directors, the members, and all authors and posters for any effects from use of any medication, supplement, vitamin or other substance, device, intervention, etc. mentioned in posts on this website, or other internet venues referenced in posts on this website.
  • We are not asking for any donations. Do not donate to any entity who says they are raising funds for us.

'Doomed' mosquitos could cut dengue infection rates

Snowy Owl

Retired in 2010, In Memoriam
<TR><TD class=headline valign="middle" colspan="2">'Doomed' mosquitos could cut dengue infection rates</TD>
http://www.scidev.net/gateways/inde...item&rgwid=2&item=News&itemid=3512&language=1
</TR><TR><TD colspan="2">
spacer.gif
</TD> </TR><TR><TD class=maintext valign="top" width="100%">
<TABLE cellSpacing=2 cellPadding=2 align=right border=0><TBODY><TR><TD class=NBK>
aedes_aegyti_eggs.jpg
</TD></TR><TR><TD width=140>
spacer.gif
The eggs of Aedes aegypti
</TD></TR></TBODY></TABLE>
Wagdy Sawahel
27 March 2007
Source: SciDev.Net
<!-- if there is an image this is the table it sits in -->

<!-- end of image table -->Scientists say that genetically modified (GM) mosquitoes, whose young die early in development, could provide a powerful means for combating dengue fever and other mosquito-borne diseases.
Sterile insects have been used for over 50 years to control or eliminate pests or disease-carrying insects such as the tsetse fly. But methods to produce sterilisation, such as radiation, are inefficient.
In research published in the journal BMC Biology last week (20 March), researchers genetically modified Aedes aegypti mosquitoes ? which spread dengue and yellow fever virus ? to carry genes that cause offspring to die either early in their development or at the later larval or pupal stages.
The researchers say that the gene causing death at the later stages of development was most effective at reducing the populations.
They mathematically modelled the impact these mosquitoes would have on a mosquito population in the wild.
The results indicated that by spreading the lethal genes, and ensuring that the offspring die before causing harm, GM mosquitoes could effectively reduce the wild mosquito population ? and thus transmission of the dengue virus ? in areas where the disease is prevalent.

"Controlling Aedes aegypti would help in the fight against chikungunya and yellow fever as well," says S. Vasan, a visiting research fellow at Oxford University, United Kingdom.
"With reasonable funding, this technology can also be extended to control other important [disease-carrying] mosquitoes including Aedes albopictus and Anopheles species."
Vasan told SciDev.Net that the mosquitoes have been tested at the Pasteur Institute in Paris, France.
He added that extensive testing was already taking place at a World Health Organization centre in Kuala Lumpur, Malaysia, and that India's Review Committee on GM is examining a proposal to conduct small-scale trials.

Paul Reiter, head of the Insects and Infectious Disease Unit at the Pasteur Institute, welcomed the development, indicating that novel approaches are urgently required to replace traditional insecticidal approaches that have little, if any, impact on disease transmission.
Dengue fever is endemic in more than 100 countries in Africa, the Americas, the eastern Mediterranean, southeast Asia and the western Pacific. The World Health Organization estimates there may be 50 million cases of dengue infection worldwide every year.
</TD></TR>
 
Re: 'Doomed' mosquitos could cut dengue infection rates

<TD valign="top" width="100%"><TABLE cellSpacing=0 cellPadding=0 width="100%" border=0><TBODY><TR vAlign=bottom><TD align=left>Research article

http://www.biomedcentral.com/1741-7007/5/11/abstract

</TD><TD align=right><!-- <rdf:RDF xmlns:cc="http://web.resource.org/cc/" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:prism="http://prismstandard.org/namespaces/1.2/basic/" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns="http://purl.org/rss/1.0/"><cc:Work rdf:about="http://www.biomedcentral.com/1741-7007/5/11"><cc:license rdf:resource="http://creativecommons.org/licenses/by/2.0/"/></cc:Work><cc:License rdf:about="http://creativecommons.org/licenses/by/2.0/"><cc:permits rdf:resource="http://web.resource.org/cc/Reproduction"/><cc:permits rdf:resource="http://web.resource.org/cc/Distribution"/><cc:requires rdf:resource="http://web.resource.org/cc/Notice"/><cc:requires rdf:resource="http://web.resource.org/cc/Attribution"/><cc:permits rdf:resource="http://web.resource.org/cc/DerivativeWorks"/></cc:License><item rdf:about="http://www.biomedcentral.com/1741-7007/5/11"><title>Late-acting dominant lethal genetic systems and mosquito control</title><dc:title>Late-acting dominant lethal genetic systems and mosquito control</dc:title><dc:creator>Phuc, Hoang K</dc:creator><dc:creator>Andreasen, Morten H</dc:creator><dc:creator>Burton, Rosemary S</dc:creator><dc:creator>Vass, Celine</dc:creator><dc:creator>Epton, Matthew J</dc:creator><dc:creator>Pape, Gavin</dc:creator><dc:creator>Fu, Guoliang</dc:creator><dc:creator>Condon, Kirsty C</dc:creator><dc:creator>Scaife, Sarah</dc:creator><dc:creator>Donnelly, Christl A</dc:creator><dc:creator>Coleman, Paul G</dc:creator><dc:creator>White-Cooper, Helen</dc:creator><dc:creator>Alphey, Luke</dc:creator><dc:identifier>info:doi/10.1186/1741-7007-5-11</dc:identifier><dc:identifier>info:pmid/17374148</dc:identifier><dc:source>BMC Biology 2007, 5:11</dc:source><dc:date>2007-03-20</dc:date>
BMC Biology</prism:publicationName>
2007-03-20</prism:publicationDate>
5</prism:volume>
1</prism:number>
Research article</prism:section>
11</prism:startingPage></item></rdf:RDF> -->.</TD></TR></TBODY></TABLE>Late-acting dominant lethal genetic systems and mosquito control
Hoang K Phuc, Morten H Andreasen, Rosemary S Burton, Celine Vass, Matthew J Epton, Gavin Pape, Guoliang Fu, Kirsty C Condon, Sarah Scaife, Christl A Donnelly, Paul G Coleman, Helen White-Cooper and Luke Alphey

BMC Biology 2007, 5:11 doi:10.1186/1741-7007-5-11

<TABLE class=smalltext cellSpacing=0 cellPadding=0><TBODY><TR><TD>Published</TD><TD width=25> </TD><TD>20 March 2007</TD></TR></TBODY></TABLE>

Abstract (provisional)


The complete article is available as a provisional PDF. The fully formatted PDF and HTML versions are in production.


Background
Reduction or elimination of vector populations will tend to reduce or eliminate transmission of vector-borne diseases. One potential method for environmentally-friendly, species-specific population control is the Sterile Insect Technique (SIT). SIT has not been widely used against insect disease vectors such as mosquitoes, in part because of various practical difficulties in rearing, sterilization and distribution. Additionally, vector populations with strong density-dependent effects will tend to be resistant to SIT-based control as the population-reducing effect of induced sterility will tend to be offset by reduced density-dependent mortality.

Results
We investigated by mathematical modeling the effect of manipulating the stage of development at which death occurs (lethal phase) in an SIT program against a density-dependence-limited insect population. We found late-acting lethality to be considerably more effective than early-acting lethality. No such strains of a vector insect have been described, so as a proof-of-principle we constructed a strain of the principal vector of the dengue and yellow fever viruses, Aedes (Stegomyia) aegypti, with the necessary properties of dominant, repressible, highly penetrant, late-acting lethality.

Conclusions
Conventional SIT induces early-acting (embryonic) lethality, but genetic methods potentially allow the lethal phase to be tailored to the program. For insects with strong density-dependence, we show that lethality after the density-dependent phase would be a considerable improvement over conventional methods. For density-dependent parameters estimated from field data for Aedes aegypti, the critical release ratio for population elimination is modeled to be 27% to 540% greater for early-acting rather than late-acting lethality. Our success in developing a mosquito strain with the key features that the modeling indicated were desirable demonstrates the feasibility of this approach for improved SIT for disease control.


</TD><TD valign="top" width="5" bgcolor="#ffffff"> </TD>
 
Re: 'Doomed' mosquitos could cut dengue infection rates

Snowy- whats the potential for unintended consequences in the processs? I applaud the efforts to reduce the population- yet based on awareness of GM corn problems, wonder if theres potential for issues with this. Any ideas?
 
Re: 'Doomed' mosquitos could cut dengue infection rates

Snowy- whats the potential for unintended consequences in the processs? I applaud the efforts to reduce the population- yet based on awareness of GM corn problems, wonder if theres potential for issues with this. Any ideas?

As we are probably witnessing unintended consequences of GM cereals (cf: Mystery killer silencing honeybees ), I do not feel comfortable with this GM mosquitoes, but since it is being developped we have to be inform.

Snowy
 
Back
Top