Brazil has become the first country to approve a single-dose dengue vaccine, marking a major milestone in the global fight against the mosquito-borne disease. The vaccine, named Butantan-DV, was developed by the Butantan Institute in São Paulo and approved by the national health regulator Anvisa for individuals aged 12 to 59. Clinical trials involving 16,000 volunteers showed 91.6% efficacy against severe dengue. The approval follows eight months of nationwide testing and is expected to accelerate immunization efforts across Brazil, which has been severely affected by dengue outbreaks. The Butantan Institute has partnered with China’s company Wuxi Biologics to produce around 30 million doses by the second half of 2026. According to the World Health Organization, dengue infects over 14.6 million people annually, causing about 12,000 deaths, half of which occurred in Brazil last year. Experts link the surge in dengue cases to global warming, which expands mosquito habitats and transmission rates.