Niteroi, Brazil, has successfully combated a dengue fever outbreak using a unique method involving the use of Wolbachia bacteria. While neighboring Rio de Janeiro has been struggling with a public health emergency due to the outbreak, Niteroi has managed to keep the number of cases significantly lower. With just 403 suspected cases of dengue so far this year and an incidence rate per capita of 69 confirmed cases per 100,000 people, Niteroi’s success is evident.
The Wolbachia bacteria, which can interrupt the transmission of the dengue virus, was introduced in Niteroi through a pilot program in 2015. This strategy was pioneered by the nonprofit World Mosquito Program and has been tested in various countries, including Australia and Brazil. The program involves breeding mosquitoes that carry the Wolbachia bacteria, effectively reducing the transmission of dengue.
Mayor Axel Grael sought help after a dengue epidemic in 2012, which resulted in thousands of notifications and one fatality. Niteroi partnered with the state-run Fiocruz Institute, the World Mosquito Program, and the Health Ministry to implement the Wolbachia technique. Since then, the number of dengue cases has significantly decreased, providing much better results for the city.
Dengue is a viral infection transmitted through infected mosquitoes. Symptoms include high fever, headaches, body aches, nausea, and a rash. While most people recover within a week, some develop severe forms of the disease that require hospitalization and can be fatal. The hot and rainy climate of Rio de Janeiro makes it particularly susceptible to dengue outbreaks.
Despite the success in Niteroi, the city continues to invest heavily in prevention measures. City health workers are sent daily to survey neighborhoods, streets, rooftops, forested areas, small businesses, and junkyards to promote best practices and eliminate standing water where mosquitoes could lay their eggs.
However, there are challenges to implementing these measures. Access is a significant issue, especially in favelas, which are often built informally and can be difficult to navigate. City agents like Augusto Cesar face the challenge of inspecting homes and removing potential breeding grounds for mosquitoes. Security is another concern, as some areas of the city are controlled by drug traffickers or militias.
The success of Niteroi’s Wolbachia program has attracted interest from other municipalities. Many are eager to implement the method on their own turf. The Health Ministry has announced plans to build a large factory to breed Wolbachia-carrying mosquitoes, with the capacity to produce 100 million eggs per week over the next decade.
Niteroi’s use of Wolbachia bacteria has proven to be an effective strategy in combating dengue fever. By interrupting the transmission of the virus, the city has managed to keep the number of cases significantly lower than neighboring Rio de Janeiro. The success of this program has sparked interest from other municipalities, highlighting the potential for widespread implementation of this innovative approach to disease prevention.
