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Stopping Malaria By Immunizing Mosquitoes
RedEaredSlider writes "Millions of people in the tropics suffer from malaria, a mosquito-borne disease that has been difficult to treat and which costs many developing countries millions of dollars per year in lost productivity. Up to now, efforts at controlling it have focused on attacking the parasites that cause it, keeping mosquitoes from biting, or killing the insects. But at Johns Hopkins University, Rhoel Dinglasan, an entomologist and biologist, decided to try another tack: immunizing mosquitoes. When a mosquito bites an infected human, it takes up some of the gametocytes. They aren't dangerous to people at that stage. Since plasmodium is vulnerable there, that is the point Dinglasan chose to attack. A mosquito's gut has certain receptor molecules in it that the plasmodium can bind to. Dinglasan asked what would happen if the parasite couldn't 'see' them, which would happen if another molecule, some antigen, were binding to those receptors."
I wonder if anyone has taken into account the population growth question that results and what the impact on poor regions like Africa that suffer most of the deaths?
.... this has the potential to equal millions more people if even a relatively small portion (25%?) go on to produce a family with 4-6 offspring.
It's been repeatedly shown that improved life expectancy and a higher standard of living lowers population growth. If you know your first two children will live relatively healthy and prosperous lives, there is a diminishing incentive to continue to produce children. The less you are sure your kids will live, the more you'd want to make some replacements just in case.
Only side effect would be not being able to eat fava beans.
If "only" that were true. As the wiki entry you linked to points out, for people with G6PD deficiency, a hemolytic anemia reaction can be induced by various drugs and chemicals (including some pretty common ones -- I once met a patient with G6PD deficiency, who apparently had an attack triggered by solvent vapors in a nail salon). Ironically enough, some of these drugs on the problem list include a number of anti-malarial agents.
Infections can also precipitate a crisis, and that's not something you can simply tell them to avoid. So unfortunately, it is a very imperfect defense against Malaria. However, so great was the historical (and in some areas, current) burden, that the advantages outweighed the drawbacks -- as they did for Sickle Cell trait, Alpha and Beta Thalessemia, Hereditary Elliptocytosis, Pyruvate Kinase Deficiency (maybe), and several others. For more information, see Genetic Resistance to Malaria as a good starting place.
Injecting mosquitoes and not killing them is pretty challenging. I work in a mosquito lab and a few members have experiments where they inject adult mosquitoes. The volume you inject is less than one microliter, which means using a glass fiber made by heating and drawing out a glass pipette which itself takes some skill to do properly. So you take a mosquito which has been on a chill plate, which renders them immobile for a while but without permanent harm, and put them on a small tube that holds them via suction. Then you have the glass fiber hooked up to a syringe with your sample, and the fiber in a holder whose position can be finely adjusted with a couple knobs. Under a low power dissecting microscope you adjust the holder to put the fiber into the mosquito's meatiest part, the flight muscles under the wings right behind the head, and inject your sample. If your fiber is too big the wound will kill the "patient," if you inject in slightly the wrong place your sample often ends up in the digestive tract, and if you inject with too much you can explode the mosquito. People in the lab who are good at it have about a 90% success rate. I'm hoping to get to do this injection procedure soon for a set of experiments. Who would turn down the opportunity to turn the tables on the little bastards and inject them with something for a change?