The Aedes aegypti mosquito is the main agent that transmits the Dengue virus that causes dengue fever. Therefore, reducing the number of mosquitoes will help lower the risk of dengue fever in the community.

Scientists believe Wolbachia bacteria - bacteria that prevent insects from transmitting some viruses - could be the solution to help reduce this disease. Beginning in the 1990s, a team of scientists led by microbiologist Scott O'Neill of Monash University, Melbourne, Australia and the director of the World Mosquito Program (WMP), developed Aedes aegypti mosquito populations infected Wolbachia in the laboratory and showed that the mosquito would not transmit viruses, including dengue virus.

Mosquitoes carrying Wolbachia bacteria are absolutely not genetically modified mosquitoes because there is no interference with the mosquito's DNA. Instead, the scientists allowed Wolbachia bacteria to infect and live symbiotically inside the animal's cells.

After that, Wolbachia is transmitted by female mosquitoes through eggs to the next generation, while male mosquitoes carrying Wolbachia, if paired with natural female mosquitoes, will produce "cancerous" eggs, thus maintaining long-term effectiveness by still reproducing naturally without increasing mosquito populations in the community.

Scientists have conducted Wolbachia mosquito release programs in many test locations in Australia and Asia, and obtained promising results.

In Vietnam, the first release of midges carrying Wolbachia bacteria was carried out on Tri Nguyen island, Vinh Nguyen ward, Nha Trang city, Khanh Hoa province in 2013. The period of 2014-2015, when Khanh Hoa was one of among dengue fever hot spots in the country, on Tri Nguyen island, only one case of dengue fever was recorded, but through investigation of medical history, this is a case that went to the mainland, got sick and then returned island again.