Figure 2From: Investigation of a recent rise of dual amantadine-resistance mutations in the influenza A M2 sequenceV27A and S31N mutations over time. Frequencies of mutation appearances relative to the total number of sequences in the subgroup (rows 1 and 2) or the total number of S31N mutants in the subgroup (row 3). Columns of panels are labelled according to the host organism associated with each sequence subset. 95% confidence intervals are indicate the grey ribbon. Years are indicated both on the bottom and the top of the figure.Back to article page