Mexico has approved the world’s first dengue virus vaccine. Sanofi’s Dengvaxia will be available to children over nine and adults 45 and under. . . Sanofi spent two decades and $1.6 billion on the development of Dengvaxia. According to BBC News, about 40,000 people in Mexico will initially receive the shot. “With this decision, Mexico moves ahead of all other countries, including France, to tackle the spread of this virus,” the country’s health ministry in a statement.