After 70 years, a vaccine for dengue

One of the grimmest legacies of the war in the Pacific is still being fought 70 years on, but a victory over dengue, the intensely painful “breakbone fever” which that conflict helped spread around the world, may be in sight.

The US Army, which like its Japanese enemy lost thousands of men to the mosquito-borne disease in the 1940s, has piled resources into defeating the tropical killer. But it may be about to see the battle to develop the first vaccine won not in the United States but by French drug company Sanofi.

The Paris-based firm hopes for positive results in September from a key trial among children in Thailand that would set it on course to market a shot in 2015 which would prevent an estimated 100 million cases of dengue infection each year. Of 20,000 annual deaths, many are of children.

For Sanofi, which has invested 350 million euros ($440 million) in a new French factory to make the three-dose vaccine, it could mean a billion euros in yearly sales as half the world is exposed to the disease, notably in fast-expanding tropical cities from Rio and Mexico to Manila and Mumbai.