Biotech firm Oxitec plans to release genetically modified mosquitoes in the Florida Keys to combat dengue fever, but critics raise concerns about the impact on human health and the environment.

This spring, the biotechnology company Oxitec plans to release genetically modified (GM) mosquitoes in the Florida Keys. Oxitec says its technology will combat dengue fever, a potentially life-threatening disease, and other mosquito-borne viruses — such as Zika — mainly transmitted by the Aedes aegypti mosquito.

While there have been more than 7,300 dengue cases reported in the U.S. between 2010 and 2020, a majority are contracted in Asia and the Caribbean, according to the U.S. Centers for Disease Control and Prevention. In Florida, however, there were 41 travel-related cases in 2020, compared with 71 cases that were transmitted locally.

Native mosquitoes in Florida are increasingly resistant to the most common form of control — insecticide.