Editing the genes of mosquitoes could make them immune to malaria or infertile. However, there are worries about the unintended consequences of releasing genetically-modified mosquitoes into the wild.

Criteria: In the next 5 years according to their list of research reports. Even a shallow review would count. Any type of gene-editing of mosquitoes would count. https://www.givewell.org/research/research-on-programs.