Dengue is sweeping through the Americas early this year

Dengue is surging across the Americas early this year from Puerto Rico to Brazil. Officials said Thursday that 3.5 million cases of the tropical disease had been reported in the region as of this week. The regional office of the World Health Organization say that's three times more cases than reported at this point last year. More than 80% of current cases are in Brazil, followed by Paraguay, Argentina, Peru and Colombia. Usually dengue spikes during the wet season which is still months away. The dengue virus is spread to people when they are bitten by infected mosquitoes.