Dengue is transmitted mainly by the Aedes Aegypti mosquito, which thrives in densely populated tropical climates and reproduces in stagnant water mirrors. It kills 10,000 people a year and infects over 100 million.
The disease is fatal only in extreme cases but the symptoms are extremely unpleasant, including high fever, severe headaches and vomiting. There is also a heavy economic burden for countries as patients are unable to work, as well as crushing health services in the event of a serious epidemic.
It is very serious – and deadly – in children, especially in girls. Scientists don't know why.
Dengue is most commonly captured by people traveling to warmer climates such as Southeast Asia, Africa, Australia, the Caribbean and South and Central America.
Prevention is vital, as it is the main way to control the disease: there are four dengue strains, which make it difficult to develop therapeutic options.
At the moment there is no specific drug to treat dengue and Dengvaxia, the first vaccine developed, is effective only in people who have already had the disease.
Researchers have announced at the beginning of this year that they expect the disease to spread throughout much of the world within the next 60 years. They say that dengue, also known as "bone fracture fever" due to the joint pain it causes, will threaten 60% of the world's population, or six billion people, by 2080.