Figure 2

Proportion of all An. gambiae caught indoors and during peak sleeping hours (9 pm to 5 am) at two sites in the Kilombero Valley in 1997 and 2004. Standard errors are not plotted as they are consistently < 0.001 for all estimates, n = 674 and 5,931 in 1997 and 2004, respectively [see Additional file 1].