In recent years, conditions in the Region of the Americas have been highly favorable for the introduction and spread of arthropod-borne viral infections (arboviral diseases). Although dengue has been circulating for over 400 years, the number of cases reported since the year 2000 represents an unprecedented increase, with four serotypes in circulation. Since that year, 19.6 million cases of dengue have been reported to PAHO/WHO, including more than 800,000 severe cases and over 10,000 deaths. In 2015 and 2016 alone, more than 4.8 million cases were reported, 17,000 of them severe, resulting in 2,000 deaths.
Despite a 23% reduction in the dengue case-fatality rate in the last six years (from 0.069% to 0.053%), the continued risk of severe disease and even death poses a serious public health problem in the Americas. Today, arboviruses present an extremely complex and unstable epidemiological situation, given the simultaneous epidemic circulation of three arboviral diseases and the risk that others could become epidemics, for example, Mayaro fever. Countries are aware that this complex situation can only be addressed with a comprehensive and multidisciplinary approach.