Neuroimaging features of arboviral infections in the Americas

Arboviruses are zoonotic RNA viruses maintained in nature in cycles that involve arthropod vectors. The arboviruses that cause disease in humans are members of the Bunyaviridae, Togaviridae, Flaviviridae, and Reoviridae families. These viral species have geographically and climatically restricted distributions due to particular ecological and vector features. The main emerging arboviruses in the Americas are dengue, zika, yellow fever (Flaviviridae), and chikungunya (Togaviridae). All of these viruses can be transmitted by the Aedes aegypti and Aedes albopictus mosquitoes. Although not commonly, these infections are associated with neurological complications, characterized mainly by hemorrhage, encephalitis, myelitis, acute disseminated encephalomyelitis, Guillain-Barré syndrome, and/or congenital malformations. This review describes the imaging features of the neurological complications of these emerging arbovirus infections. •The most important emerging arbovirus infections in the Americas are Dengue, Chikungunya, Zika and Yellow Fever.•Dengue can be complicated by hemorrhages, encephalitis, and immune-mediated syndromes, such as ADEM and Guillain Barré.•Chikungunya can be associated with encephalitis, myelitis, immune-mediated diseases and perinatal transmission.•Neurologic complications are associated with Zika virus infection, both when acquired before and after birth.•Although vaccine against Yellow fever is safe, cases of adverse neurological symptoms such as ADEM have been reported.