Fig. 5From: The impact of an 8-year mass drug administration programme on prevalence, intensity and co-infections of soil-transmitted helminthiases in BurundiYearly semivariograms for hookworm infection (in decimal degrees). Each plot shows a semivariogram for each year of the impact study: a2007, b 2008, c 2009, d 2010, e 2011, f 2014Back to article page