http://www.travelmedicinejournal.com/article/S1477-8939(15)00173-8/pdf

In early 2015 it was reported several cases of Dengue and Chikungunya virus infections in various Brazilian states. Some states have been reported Zika virus cases has symptoms very similar to the symptoms of Dengue. A hypothesis that the virus Zika has spread by Brazil in the World Cup 2014 due to the large number of foreign tourists and the virus in circulation have been identified as Asian genotype through phylogenetic analysis. Because of all this viral priate it is necessary to provide greater control and supervision of borders, due to the increase of foreign travelers to the 2016 Olympic Games in Rio de Janeiro, Brazil.