*Anti-malaria mosquito could save millions of lives / **Researchers Engineer Mosquitoes into “Flying Vaccinators”*
[image: 090421-world-malaria-day_170.jpg] by NICK MCDERMOTT and LUCY BALLINGER *Scientists believe a genetically engineered mosquito resistant to malaria could lead to the virtual eradication of the deadly disease.* They hope the GM variety, which outlives its unmodified rivals, will dominate in the wild and prevent the spread of the deadly parasite. The disease, which is passed on to humans through the female insect's bite, affects 300million victims every year. U.S. scientists have engineered a mosquito which cannot be infected by the parasite and laboratory tests showed it has a greater chance of survival. The researchers said: "The results have important implications for implementation of malaria control." Malaria - spread by the single-celled parasite Plasmodium - is endemic in parts of Asia and central and south America. It is estimated it causes 2.7million deaths a year - and a child dies of the disease every 30 seconds in sub-Saharan Africa. British experts welcomed the research but warned that extensive tests were needed before the insects are released into the wild. Dr Mark Enwright, senior research fellow in microbiology at the University of Bath, said: "It is promising, but we would have to be careful of what the consequences were of putting these mosquitoes into the wild. "The malaria parasite could well evolve and infect these mosquitoes - then you would have a super-insect which is immune to other things too." In experiments carried out by researchers at Johns Hopkins University in Maryland, equal numbers of the modified and ordinary mosquitoes were allowed to feed on malariainfected mice. The modified mosquitoes had a higher survival rate and laid more eggs. After nine generations, 70 per cent of the insects belonged to the malaria-resistant strain. The scientists, led by Dr Mauro Marrelli, reported their findings in the journal Proceedings of the National Academy of Sciences. They said it was the first time anyone had produced genetically-engineered mosquitoes which lived longer. For resistant mosquitoes to be useful in the wild, they must out-compete non-resistant rivals - even when no malaria is present. So the scientists were pleased to find that even when both sets of insects were fed noninfected blood their survival rate was the same. The researchers said that if modified mosquitoes became dominant, the malaria parasite would find it difficult to re-establish itself in places where it had been eradicated. *Genetically modified mosquitos may help fight malaria* *Japanese scientists have developed a genetically modified mosquito that vaccinates as it bites and could help prevent the spread of malaria.* *The research team has created an insect producing a natural vaccine protein in its saliva, which is injected into the bloodstream when it bites. * *The “prototype” mosquito carries a vaccine against Leishmania, another potentially fatal parasite disease spread by sand flies, reports dailymail.co.uk. * *Leishmania infection can cause painful sores, fever and weight loss and if untreated may destroy the liver and spleen. * *The findings revealed that mice bitten by the vaccinating insect generated antibodies against the Leishmania organism, indicating immunisation. * *“Following bites, protective immune responses are induced, just like a conventional vaccination but with no pain and no cost,” said study leader professor Shigeto Yoshida, from Jichi Medical University in Shimotsuki, Japan. * *“What’s more, continuous exposure to bites will maintain high levels of protective immunity, through natural boosting, for a life time. So the insect shifts from being a pest to being beneficial,” Yoshida added. * *Scientists are still working on developing an effective malaria vaccine, so Yoshida’s study was very much a “proof of concept”. * *However, ethical considerations may also get in the way of using “flying vaccinators” to control malaria, he said. * *The study was published in the journal Insect Molecular Biology.* *Experts believe ''flying vaccinators'' could be a radical new way of tackling malaria. * *However, a strategy that allows the uncontrolled mass delivery of vaccines via biting insects could raise ethical objections. * *Each year malaria claims between one and two million lives around the world, mostly of African children. * *The disease is caused by a single-celled parasite spread by the Anopheles mosquito. * *Scientists have looked at a number of ways of genetically modifying the insect to stop it transmitting the organism. * *They include making male mosquitoes infertile, and creating a malaria-free insect that will out-survive the carriers. * *The new approach, the most radical yet, targets the salivary gland of the Anopheles mosquito. * *Scientists in Japan have engineered an insect producing a natural vaccine protein in its saliva which is injected into the bloodstream when it bites. * *The ''prototype'' mosquito carries a vaccine against Leishmania, another potentially fatal parasite disease spread by sand flies. * *Leishmania infection can cause painful sores, fever and weight loss and if untreated may destroy the liver and spleen. * *Mice bitten by the vaccinating insect generated antibodies against the Leishmania organism, indicating immunisation. * *''Following bites, protective immune responses are induced, just like a conventional vaccination but with no pain and no cost,'' said study leader Professor Shigeto Yoshida, from Jichi Medical University in Shimotsuki, Japan. * *''What's more, continuous exposure to bites will maintain high levels of protective immunity, through natural boosting, for a life time. So the insect shifts from being a pest to being beneficial.'' * *The research is reported in the journal Insect Molecular Biology. * *Scientists are still working on developing an effective malaria vaccine, so Prof Yoshida's study was very much a ''proof of concept''. * *Ethical considerations may also get in the way of using ''flying vaccinators'' to control malaria, he said. * *Such a strategy would involve the mass delivery of a vaccine without first obtaining the consent of patients or monitoring dosages. * *K.Raman. * To unsubscribe from this group, send email to thatha_patty+unsubscribegooglegroups.com or reply to this email with the words "REMOVE ME" as the subject.
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