At least 100 more resources are being used for dengue than for mosquitoes, unfortunately for dengue having "near perfect" protection (the normal situation for all other vaccines) is not only not effective, it actually produces a worse disease. For better or worse controlling dengue is going to take a few more billions and at least one more decade. Also, you control the mosquito and you control several diseases at the same time.
The problem in this case is not so much the danger of the genetic manipulation (the approach seem to be based in minimizing risk) but seen how effective it is really going to be in a large scale situation. People worry much more about this being a waste of money than a danger to the ecology.
Also, the process specifically make the females produced by this males to become sterile so for one part you will get slowly more and more gene-carrier males competing for the healthy females (that will be less and less frequent) in every generation, it will have the extra merit of making the affected females less prone to bite so the risk to humans dimish.
Anyway, the good thing is that this approach affects only a single species of mosquito so even if this goes out of control you have very few risk to the ecology, compared with other much more risky trials (like those done with the Wolbachia parasite in Australia) this seems to be relatively safe.