Figure 2. Results from a serologic study of the 2007 epizootic wave of bluetongue virus serotype 8 (BTV-8) in France among cattle herds from an east–west transect of 6 departments (codes 18, 41, 36, 37, 49 and 35) and from the first department to report BTV-8 infection in 2006 (code 08). Circles, herd-level anti–BTV-8 seroprevalence rate; squares, animal-level seroprevalence rate; triangles, proportion of seropositive herds having reported confirmed clinical cases in 2007; box plots, distribution of within-herd seroprevalence rates. Thick horizontal lines represent the median value of the distribution. Rectangles represent the 25th and 75th percentiles. Error bars represent the maximum and minimum values observed in the distribution.