For the first time, scientists have developed an early warning system to predict the risk of dengue infections for the 553 microregions of Brazil during the football World Cup. The estimates, published in The Lancet Infectious Diseases, show that the chance of a dengue outbreak is enough of a possibility to warrant a high-alert warning in the three northeastern venues of Natal, Fortaleza, and Recife but is likely to be generally low in all 12 host cities.
Dengue is a viral infection that is transmitted between humans by Aedes aegypti mosquitoes. In some cases, it causes life-threatening illness. There are currently no licensed vaccines or treatments against dengue. So far this century, Brazil has recorded more cases of dengue fever than anywhere else in the world, with more than 7 million cases reported between 2000 and 2013.
“Recent concerns about dengue fever in Brazil during the World Cup have made dramatic headlines, but these estimates have been based solely on averages of past dengue cases. The possibility of a large dengue fever outbreak during the World Cup, capable of infecting visitors and spreading dengue back to their country of origin, depends on a combination of many factors, including large numbers of mosquitoes, a susceptible population, and a high rate of mosquito-human contact,” explained lead author Rachel Lowe from the Catalan Institute of Climate Sciences in Barcelona, Spain.
The researchers estimate little risk of dengue outbreaks during the forthcoming World Cup period in the southern and central capitals of Brasília, Cuiabá, Curitiba, Porto Alegre, and São Paulo. However, they predict that there is some chance of dengue risk exceeding medium levels in Rio de Janeiro, Belo Horizonte, Salvador and Manaus. The three cities with the highest risk are Natal, Fortaleza, and Recife, although the risk still remains relatively low.