Figure 6.13 Velocity of epidemic waves in Iceland for the influenza... | Oxford Medicine Online

Figure 6.13 Velocity of epidemic waves in Iceland for the influenza seasons 1915–16 to
1975–76. (A) Velocities of the leading edge (LE, solid lines) and
following edge (FE, pecked lines) are shown as the velocity ratios,
VLE and VFE, defined in Appendix
Appendix 6.1: Swash–Backwash Model Equations
6.1 equation (A2). V is in the range, 0 ≤ V ≤ 1. The larger
the value of V, the faster the edge. (B) The widening time gap between the
two edges illustrated in (A) is confirmed in this graph which plots the average
duration of each district’s epidemic wave in months. In both (A) and (B) the trend
lines were determined by OLS linear regression.

Source: All influenza data based on Heilbrigðisskýrslur (Public
Health in Iceland)