Cutting Mosquito Lifespans To Curb Disease
Researchers Use Parasite To Trim Life To 21 Days; Older Insects Spread Malaria, Dengue
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Because older mosquitoes spread diseases like malaria and dengue fever, scientists have been racing to find ways to make mosquitoes die younger as an alternative to mass sprayings of insecticide. (AP Photo)
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Scientists have been racing to genetically engineer mosquitoes to become resistant to diseases like malaria and dengue fever that plague millions around the world, as an alternative to mass spraying of insecticides.
A new report Friday suggested a potentially less complicated approach: Breeding mosquitoes to carry an insect parasite that causes earlier death.
Once a mosquito encounters dengue or malaria, it takes roughly two weeks of incubation before the insect can spread that pathogen by biting someone, meaning older mosquitoes are the more dangerous ones.
The Australian scientists knew that one type of fruit fly often is infected with a strain of bacterial parasite that cuts its lifespan in half.
So they infected the mosquito species that spreads dengue fever - called Aedes aegypti - with that fruit-fly parasite, breeding several generations in a tightly controlled laboratory.
Voila: Mosquitoes born with the parasite lived only 21 days - even in cozy lab conditions - compared to 50 days for regular mosquitoes, University of Queensland biologist Scott O'Neill reported in the journal Science.
Mosquitoes tend to die sooner in the wild than in a lab. So if the parasite could spread widely enough among these mosquitoes, it "may provide an inexpensive approach to dengue control," O'Neill concluded.
Theoretically, it could spread: This bacterium, called Wolbachia, is quite common among arthropod species, including some mosquito types - just not the specific types that spread dengue and malaria, the researchers noted. And Wolbachia strains are inherited only through infected mothers, with an evolutionary quirk that can help them quickly gain a foothold in a new population.
Next month, O'Neill's team begins longer studies in special North Queensland mosquito facilities that better mimic natural conditions to see how well the wMelPop strain persists as more mosquitoes are born, and what happens when they're exposed to dengue.
"By killing old mosquitoes, wMelPop could thus impact on dengue transmission," Pennsylvania State University specialists Andrew Read and Matthew Thomas concluded in an editorial accompanying the work, which they called "a major step."
It's possible that dengue viruses could evolve to incubate more rapidly if their mosquito hosts die younger, they noted, although that likely would be less of a problem than today's insecticide resistance.
Still, "determining whether it can remove enough infectious mosquitoes to be useful will be a challenge," the duo cautioned.
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Best-selling author Mitch Albom on his first nonfiction work since "Tuesdays with Morrie."





Personally, as much as I dislike this position, I think it''''s too late for Poalr Bears in the wild. It''''s not possible to stop the ice melt each season in the Artic now.
Posted by HSinCO
The new Depression is here and states will not be worried about Polar Bears when they cannot afford fuel for their plow trucks. Ask California...lol
Posted by DebinOK1 at 11:34 PM : Jan 01, 2009
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Having grown up in extreme East Texas, Beaumont-Port Arthur, I don''''t see a problem here with mosquitos becoming extinct. These things also carry canine heart worms, as well as malaria, dengue, and a host of other viral and bacterial agents.
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Posted by docpeter1953 at 08:35 AM : Jan 02, 2009
How many mosquitios are there and how many Polar Beras are there? The mosquito population needs to be cut and the Polar Bear population needs to be enhanced.
Personally, as much as I dislike this position, I think it''s too late for Poalr Bears in the wild. It''s not possible to stop the ice melt each season in the Artic now.
My college tinkered with "Love Bugs" to control mosquitos in FL. The only problem is in didn''t work at all. It started with one week per year that the state was infested with love bugs. Now it''s twice a year and lasts for 3 weeks! Nothing can stop Them!
Posted by DebinOK1 at 11:34 PM : Jan 01, 2009
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Having grown up in extreme East Texas, Beaumont-Port Arthur, I don''t see a problem here with mosquitos becoming extinct. These things also carry canine heart worms, as well as malaria, dengue, and a host of other viral and bacterial agents.
Posted by DebinOK1
Read the article again, dufus !
Messing with Mother Nature can backfire...
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Posted by mahdeealoo at 07:40 PM : Jan 01, 2009
My thoughts exactly!
- by mahdeealoo January 1, 2009 10:40 PM EST
- As long as it doesn''t infect other insects that are a viable source of food for bats, birds, and other insect eating species that curb insects on the planet. Like bees.
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See all 14 CommentsMessing with Mother Nature can backfire...