Betim begins releasing Wolbachia mosquitoes to combat dengue

The city of Betim has begun releasing ‘Wolbitos’—Aedes aegypti mosquitoes carrying the Wolbachia bacteria—as part of a strategic effort to combat arboviruses such as dengue, chikungunya, and zika. The initiative is a partnership between the World Mosquito Program (WMP) Brasil, through the Fundação Oswaldo Cruz (Fiocruz), the Betim City Hall, and the Government of Minas Gerais.

When these mosquitoes mate with the local population, they transmit the Wolbachia bacteria to subsequent generations, which reduces the insects' ability to transmit viruses. Scientific studies suggest this method can reduce dengue cases by up to 89%. The process does not involve genetic modification and is considered safe for humans, animals, and the environment.

The first phase targets five neighborhoods—Jardim Teresópolis, Santo Antônio, Vila Boa Esperança, Amazonas, and Renascer—based on technical criteria including infestation rates and case numbers. The mosquito releases, produced in a biofactory in Belo Horizonte, are scheduled to occur on Wednesdays starting at 5:30 a.m., with the work expected to last between 16 and 20 weeks per area. The program is funded by resources from the Brumadinho judicial agreement.