Simultaneous circulation of arboviruses and other congenital infections in pregnant women in Rio de Janeiro, Brazil

Background Arboviruses (Zika, dengue and chikungunya) represent a major risk for pregnant women, especially because their vertical transmission can lead to neurological damage in newborns. Early diagnosis can be difficult due to similar clinical presentation with other congenital infections that are associated with congenital abnormalities. Objectives To investigate the circulation of arboviruses and other pathogens responsible for congenital infections, reporting clinical aspects and geographic distribution of maternal rash in a metropolitan region of Rio de Janeiro (Brazil). Methods Cross-sectional study with pregnant women presenting rash attended at the Exanthematic Diseases Unit (Niteroi, Rio de Janeiro) from 2015 to 2018. Diagnosis of arboviruses was performed by real-time PCR (RT-qPCR) and laboratorial screening for syphilis, toxoplasmosis, rubella, cytomegalovirus and HIV was assessed. Demographic data was used for georeferencing analysis. Findings We included 121 pregnant women, of whom Zika virus was detected in 45 cases (37.2%), chikungunya in 33 (27.3%) and dengue in one (0.8%). Five patients presented syphilis, and we observed one case each of listeria, cytomegalovirus, and a syphilis-toxoplasmosis case. Similarity of clinical symptoms was observed in all groups; however, 84.8% of patients with chikungunya presented arthralgia. Following the decline of Zika cases, chikungunya infection was mostly observed during 2017–2018. Considering pregnant women infected with arboviruses and other infections, 41% resided in urban slums, mostly in Niteroi. Main conclusions Simultaneous circulation of arboviruses and other agents responsible for congenital infections were observed; however, we did not identify co-infections between arboviruses. In this scenario, we emphasize the importance of adequate prenatal care to provide an accurate diagnosis of maternal rash.