Notícias

Transgenic mosquitoes are the new tool to control Aedes aegypti population

Despite technologys benefits, the use of these insects could still be expensive for the public health network

25/10/2015
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Soon the Good Aedes aegypti will be used in places where the risk of an outbreak is greater, or where the current tools have proved to be ineffective

The creation of a genetically modified mosquito, also known as the transgenic mosquito, has been broadly diffused in Brazil. The technology, currently being inserted in Brazil, aims to control the population of the transmitter of dengue, the Aedes aegypti, and decreasing the cases of the disease in the Country.

According to Margarth Capurro, PhD in Biology, one of the benefits of using the transgenic mosquito is the decrease in the use of insecticides. Using the modified mosquito has always been thought of as a way of integrated control. If there is a mosquito that will naturally decrease the population, then there is no need to use insecticides, which is very toxic, explained.

Besides this, for the doctor, the Aedes aegypti is a plague that would cause no environmental impact if eradicated. It is not native to Brazil. It has already been eliminated during yellow fever campaigns and then was reinserted, she said. Its ecology is urban, which is the reason it is considered a plague. It is totally associated to humans. There is no environmental impact, even if it is eradicated, she completed.

Implementation feasibility

According to Dr. Margareth Capurro, one of the main difficulties using transgenic mosquitoes – as those developed by British company Oxitec – is the used lineage, currently made by separating males and females. One of the advantages we found during tests was a field to develop new lineages, allowing to use those more adequate for a system in Brazil, she pointed. Still according to her, there is an attempt to enhance the project and make it cheaper and more efficient.

However, the doctor said, the current lineage would generate a very high cost as a public health program. This is because, currently, only about 25% of the production is utilized, and the rest is discarded. What happens is that today, we have a vision of what could be enhanced in the lineages, so we are able to use 100% of the production, she stressed.

The technology

Oxitec created the OX513A mosquito, known as Good Aedes aegypti. The insect can be used anywhere the mains transmitting vector of dengue, chikungunya and zika virus is present. During the next few years, we will keep focus on the Good Aedes aegypti in places where the risk of outbreaks is greater or where the current tools have proved to be ineffective to control the wild mosquito, explained Oxitec Brazils president, Glen Slade.

The technology is already in use in Jacobina, Bahia and Piracicaba, Sao Paulo. Now, the idea is to expand the use of the transgenic mosquito. We are in touch with the different divisions of the Brazilian government to expand the use of Good Aedes aegypti. Unfortunately, until now, the Sanitary Surveillance Agency (Anvisa) has not responded our requests on which documents we must provide to request its commercial use. This way, our options to increase the use of this safe, effective and environment friendly solution become ever more restricted, he deplored.

Regarding the results of the use of these mosquitoes, Oxitecs director said that besides Juazeiro and Jacobina in Bahia, the Good Aedes aegypti suppressed dengues transmitting mosquito in East End, in the Cayman Islands by 96% and in Nuevo Chorrillo, in Panama, by 93%.

How does it work

Though genetics and molecular biology, Oxitec inserted a lethal gene to create a lineage of Genetically Modified Organisms (GMOs). These male GMOs, when released in the wild, instinctively find wild females (responsible for dengues transmission). Their offspring die before reaching adulthood, what leads to a decrease in the plague insects population.…