The periodicity of Plasmodium vivax and Plasmodium falciparum in Venezuela

The monthly time series of Plasmodium vivax incidence (below) in southern Venezuela (1990-2010) and the corresponding wavelet power spectrum (above) showing cycles of 3-6 years (period). Malaria cases intensifies approximately 1 year after El Niño events (red arrows) highlighting the role of climate inter-annual variability in the epidemic patterns of this disease in Venezuela.