Impact of timing on the effectiveness of different vaccination strategies. Vaccination campaigns were implemented weekly, starting July 5, 2009, with the last campaign started November 22, 2009. For a given campaign start date, the reduction in a final attack rates and b mortality relative to no vaccination was assessed using actual (blue, solid line), uniform (green, dashed line), parents and children only (red, dash-dotted line), or parents and children only/actual sequence (cyan, dotted line) vaccination strategies. All simulations assumed R
0 of 1.4, latent period of 3 days, infectious period of 7 days and an 8-week vaccine roll-out period.