Comportamento dinâmico da febre amarela silvestre no Brasil (1954-2008)

Abstract

Introduction: Sylvatic yellow fever (SYF) is enzootic in Brazil, causing periodic outbreaks in humans living near forest borders or in rural areas. In this study, the cycling paterns of this arbovirosis were analyzed. Methods: Spectral Fourier analysis was used to capture the periodicity paterns of SYF in time series. Results: SYF outbreaks have not increased in frequency, only in the number of cases. Tere are two dominant cycles in SYF outbreaks, a seven year cycle for the central-western region and a 14 year cycle for the northern region. Most of the variance was concentrated in the central-western region and dominated the entire endemic region. Conclusions: Te seven year cycle is predominant in the endemic region of the disease due the greater contribution of variance in the central-western region; however, it was possible identify a 14 cycle that governs SYF outbreaks in the northern region. No periodicities were identifed for the remaining geographical regions.