This year Brazil hosts the 20th FIFA World Cup, attracting up to half a million international visitors. For the areas around nine of the World Cup stadiums, records show that the main dengue season will have passed before the World Cup is held in June and July, although the risk remains in the northeast.
Still, the mass gatherings of fans may increase the potential for dengue transmission and supporters could introduce new genotypes to which local immunity is low.
It has been suggested that the Brazilian authorities should implement aggressive vector control in April and May, particularly around the northern stadiums, to decrease the number of dengue-transmitting mosquitoes. However the matches play out, the World Cup is at least an opportunity to evaluate the uptake of new public health information systems on dengue so they can be enhanced in the future and potentially applied in other countries.