It seems that at least some of the reason why malaria is so prevalent in sub-Sahara Africa has to do with poor housing, poor management of drainage / sewers, and poor roads.
http://www.hindawi.com/journals/jtm/2012/819563/
I'm not ruling out eliminating mosquitoes per se, but the United States and Europe managed to largely eliminate malaria in the 1930s-1940s without eliminating mosquitoes. So before I'd start advocating the elimination of entire subsets of species, I'd ask how the US and Europe were successful in their efforts, and wonder why we can't apply those lessons to the rest of the world. Maybe the money spent in targeting the elimination of mosquitoes (which cause a lot of problems) would be better spent in general health and sanitation (the lack of which also causes a lot of problems), for instance.
I'm all for releasing CRISPR on the worst species of mosquitos though. And ticks. They can't serve any function other than killing a few persons each year due to TBE.
Why does there have to be a region in permanent squalor? Why can't every place on earth where civilization exists be a decent place for humans to live, with peace, opportunity and sanitation?
But ... back down to earth. Since we can't fix that larger problem, at least maybe we can stop malaria by killing all the mosquitoes.
Seems to me that good second-world sanitation might alleviate it. But third world countries lack the sanitation and hence suffer Malaria. Seems the problem is political/social.
Coincidentally, there are quite many areas in Sweden were it is impossible to go outside in the summer without mosquito nets, and it is worsening.
Mosquitoes do exist in Europe; they don't spread malaria because it isn't there to spread, and it isn't there to spread because of effective healthcare.
(Europe isn't a great example as the mosquito population is not exactly high, which I guess is climate-related, but the above is also true of parts of the developed world where their populations are higher)
Mosquitos occur world-wide, and even flourish in many climates where rates of infection from mosquito-borne diseases are relatively low. As an example, 90% of deaths from Malaria occur in sub-Saharan Africa, and even there, the likelihood of death from infection is radically lower for western visitors than for locals.
These diseases are largely a result of poverty and poor access to healthcare, not of mosquitos.