Understand how genetically modified dengue mosquitoes work

In the pilot program, the city of Piracicaba chose the CECAP/El Dorado neighborhood to receive the product and try to control the dengue epidemic at that time, where there were 133 cases among five thousand people. The Alvorada neighborhood, which served as a reference to compare the effectiveness of the program and did not receive the modified mosquitoes, was 2 km away. The areas had similar characteristics in terms of building type, basic sanitation, and population density.

Modified mosquitoes were released three times a week. In the first year, 45 million mosquitoes were released; In the second, 30 million; And in the third, 13 million. In the first peak of the rainy season, the period when transmitters reproduce most easily, the number of larvae in traps was seven times lower in the CECAP/Eldorado neighborhood than the number observed in the control neighborhood, Alvorada. The reduction in mosquito numbers was 79%. With the positive result, the researchers reduced the release of new vectors by 33%.

In the second rainy season, between 2016 and 2017, the prevalence of wild mosquitoes continued to decline by 81%. In the third station, the suppression rate reached 76%. During this period, neighborhoods had no access to pesticides of chemical origin.

In another case study, tests were conducted in the city of Indayatuba, also in São Paulo, in 2018, with the second generation of the product. The project covers 12 neighborhoods with an area of ​​45 thousand people. After five years of probation The average reduction in Aedes aegypti numbers in treated areas was 96%..

Between 2011 and 2015, the company also conducted tests in two cities within Bahia: Jacobina and Juazeiro. The research was conducted by scientists from the University of São Paulo in collaboration with Biofábrica Moscamed Brasil, the country's first fly factory. The factory was established in 2006 with the aim of carrying out biological control of the Mediterranean fly, a pest of Brazilian fruit cultivation, using sterilized insects. In both municipalities, the pilot project identified a more than 90% reduction in Aedes aegypti populations after the release of the modified mosquitoes.

A technical opinion issued by CTNBio in 2020 certified that the program “is not likely to cause significant degradation to the environment or human health.” In the same year, the program was tested in Florida in the United States, and it also posed no biosafety risks, ensuring approval by the country's Environmental Protection Agency. The results of the experiment have not yet appeared in the United States, and the study is still ongoing.