Aedes aegypti in Brazil
Aedes aegypti is a non-native species in Brazil and is responsible for spreading serious viral diseases such as dengue, Zika, chikungunya and yellow fever. Together these viruses infect hundreds of thousands of Brazilians every year, with devastating consequences.
As Aedes aegypti is particularly difficult to control as it lives around humans and has become resistant to many insecticides, cities in Brazil are looking for new technologies to suppress the population of these disease carriers.
We have been successfully releasing our self-limiting Friendly™ Aedes solution in Brazil since 2011, and successfully completed the first field deployment of Oxitec’s 2nd Generation Friendly™ Aedes aegypti, called ‘OX5034’, in 2019 in the city of Indaiatuba, São Paulo state.
Read more about how our solution works here.
In 2019, we completed the first field trial in Brazil of the 2nd Generation Friendly™ Aedes aegypti, OX5034. In partnership with the municipal vector control authorities in the city of Indaiatuba, the pilot project demonstrated the new strain’s effectiveness in suppressing populations of Aedes aegypti in four densely populated urban communities across the city relative to an untreated site.
Releases of OX5034 male mosquitoes were conducted in four separate communities under approval issued by Brazil’s national biosafety authority, CTNBio, during a year-long trial starting in May 2018. The trial was designed to test a number of performance features of the 2nd Generation Friendly™ technology, including the performance outcomes generated by the use of two different mosquito release rate levels in dense urban environments. Abundance of wild Aedes aegypti was monitored before and during the release program to allow for an accurate evaluation of the trial’s impact. Wild Aedes aegypti numbers were kept at low levels throughout the high season in all treated neighborhoods, whereas populations in areas untreated by Oxitec’s Friendly™ Aedes aegypti rose as normal.
Relative to the untreated control area, releases of Friendly™ male mosquitoes achieved an average of 89% peak suppression across two communities treated with a low release rate of mosquitoes and an average of 93% across two communities treated with a higher release rate. The optimal suppression observed was in one community wherein a 96% peak suppression with the high release rate over a 4-week period was achieved.
Previous projects in Brazil
All previous field deployments have been with Oxitec’s 1st Generation Aedes aegypti, OX513A.
In a successful 4-year program in the city of Piracicaba, starting with treating an area with 5000 residents and expanding to include 11 additional neighborhoods home to a further 60,000 residents, releases of our Friendly™ OX513A mosquitoes achieved 83% or greater suppression annually, and up to 98% suppression, as compared to untreated sites.
Juazeiro and Jacobina
Between 2011 and 2015, our Friendly™ OX513A mosquitoes were subject to extensive pilot studies in Brazil by independent collaborators Moscamed and the University of São Paulo. Trials took place in the neighborhoods of Itaberaba and Mandacaru in Juazeiro, and in Jacobina.
In these successful releases of our Friendly™ mosquitoes reduced the wild population by 90+%, compared to a control area that was not treated with our mosquitoes. More information is available in this published paper.