Figure 2From: The first wave of pandemic influenza (H1N1) 2009 in Germany: From initiation to acceleration Activity of acute respiratory illness and school holiday density between week 18 and 45, Germany 2009. Weekly data of Practice index in Germany. Threshold >115. (dotted line) Arbeitsgemeinschaft Influenza, Robert Koch Institute. Light blue columns indicate the vacation density for each week.Back to article page