Can't find fault there. However, by reducing the lifespan of the anopheles mosquito by an amount sufficient to disrupt the life-cycle of the parasite it carries.. does that not invite another organism to move in and take the place of the anopheles? I honestly don't know.
But, fair enough. This is wave-of-the-wand stuff, so, yeah, plasmodium is gone in your world. As far as I know, nothing depends on it as a food source, so yeah, it's toast!
No. Here's the way it works. Well, the basics, anyway.
Every female adult anopheles starts out clean, without the parasite. It must pick up the parasite from a parasite carrying human by taking a blood meal. The blood is required for its eggs to develop. The parasites are not. Not every meal (human) carries the parasite. The mosquito can only transmit the the plasmodium parasite after it itself has been infected. Typically, in the wild, the female mosquito lives 7-14 days, (can be more, can be less, depending on conditions) which means that the female anopheles takes somewhere between 1-4(+) blood meals.
The female that takes 1 blood meal is a non factor. Even if the human that it feeds on was infected and transmitted the parasite to the mosquito, the mosquito never transmits the parasite to a human. This mosquito is a transmissive dead end. And remember, not every human it takes a meal from is a host.
With each successive human it takes a meal from, the chances increase that the mosquito picks up the parasite. So the really dangerous mosquitos are the older mosquitos, the ones that have poked multiple humans.
Furthermore, the parasite takes time to develop and travel through the mosquito for the mosquito itself to become transmissive, which depending on the environmental conditions, can be anywhere from one to three weeks.
So if you reduce the overall lifespan by just a fraction, you reduce the number of dangerous, transmissive mosquitoes and at a given point for a given environment, and you reduce overall transmission. Which reduces the number of human carriers, which reduces the number of mosquitos that pick up the parasite, so on. Every environment has a certain point on the curve at which the problem more or less solves itself. The idea is to force the mosquito into a faster adult life cycle. Larvae, we don't care so much about. They might actually be useful and fulfill an ecological niche that we haven't really studied.
That's the principle, anyway.
/epi lecture for the day
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