Epidemiology, genetic diversity and clinical manifestations of arboviral diseases in Venezuela

Arthropod-borne viruses (arboviruses) are pathogens causing high morbidity and mortality among humans and domestic animals worldwide. Arboviruses were considered in the past as unimportant causative agents of human disease. This conception has changed due to their continued emergence and re-emergence, and nowadays they are recognized as public health threats. Venezuela, in the Americas region, is one of the countries affected by the emergence/reemergence of arboviruses (i.e. Zika and chikungunya) and the continued transmission of dengue virus.
Venezuela is endemic for dengue with the co-circulation of the four DENV serotypes and is one of the countries with the highest proportion of severe cases in the Americas (PAHO, 2018). The epidemics of chikungunya in 2014 and Zika in 2016 swept the country causing a high burden of disease. These facts highlighted the need for a better understanding of the epidemiological and molecular dynamics of these concurrent arboviral diseases, and the need for accurate differential diagnosis. Our work provides a detailed epidemiological and spatial-temporal characterization of the introduction of a new arbovirus, chikungunya virus (CHIKV), into the country, coinciding with an outbreak of an endemic virus (dengue), sparking the question of differential diagnosis. In addition, our work provides an update on the (molecular) epidemiology and evolution of DENV viruses in Venezuela where we follow the circulating lineages and their frequency, and explored DENV intra-host variability.