Zika virus displacement by a chikungunya outbreak in Recife, Brazil

Infection with Zika (ZIKV) and chikungunya (CHIKV) viruses can lead to severe symptoms or outcomes. These viruses are transmitted by the same mosquito vectors that transmit dengue virus (DENV) and the symptoms of all three diseases are similar, thus, it may be difficult for health professionals to diagnose them properly. This study was part of larger study aimed at improving the diagnosis of these diseases. We present data on a patient cohort from Recife, Brazil in which the majority of patients were infected with ZIKV or CHIKV. We show that when Zika cases started to decrease, chikungunya cases appeared and increased rapidly, remaining high until the end of the study. We also highlight the high levels of cross-reactivity on dengue serological assays with ZIKV-positive samples, emphasizing the importance of choosing appropriate tests in areas with simultaneous circulation of arboviruses. Other important epidemiological data are shown and discussed, such as the differential proportion of women and men infected with ZIKV or CHIKV, and the identification of strong hotspots of chikungunya cases. These data may help on the development of control and prevention interventions against arboviral diseases. http://journals.plos.org/plosntds/article?id=10.1371/journal.pntd.0006055