The mosquito Aedes aegypti is the main vector for dengue fever (also known as breakbone fever), a disease caused by the dengue virus. WHO estimates that there are between 50-100 million cases of dengue fever each year with 2.5 billion people at risk. Genetic strategies are being developed with the aim of decreasing the ability of the mosquito to transmit the disease. That is rather than eradicate Ae. aegypti, the goal is to replace existing populations with a mosquito population that cannot transmit the dengue virus. Fred Gould and colleagues at NCSU have developed a model called “killer-rescue” for how to spread an anti-viral genetic system through an Ae. aegypti population. We are interested in developing and testing potential “killer-rescue” systems in genetically engineered Ae. aegypti.