In one or two people out of every 100,
dengue can progress to a more serious illness which can be fatal.2
This is called severe dengue.
Dengue occurs in more than 100 countries and is widespread in tropical and sub-tropical climates.3
The number of cases is increasing as dengue spreads to new areas where the mosquitoes that transmit the virus are present, including Europe. Larger outbreaks are occurring even outside of regions where the virus is prevalent.