Fig. 2From: Chronological, geographical, and seasonal trends of human cases of avian influenza A (H5N1) in Vietnam, 2003–2014: a spatial analysisSeasonal variation during the entire observational period (2003–2014) was tested by Roger’s statistic (p < 0.001). The p values for each period were p < 0.001 in the outbreak period (2003–2005), p = 0.059 in the post-outbreak period (2006–2009), and p < 0.001 in the recent period (2010–2014)Back to article page