Figure 2).
(a) Attack rates of the sensitive strain (dashed curve), the resistant strain (dotted curve) and both strains (solid curve), when only a single drug (eg, oseltamivir) is used during the entire outbreak. The overall attack rate is minimized at 52% of the treatment level (fc=0.52) within the intermediate range of 40% to 60%. (b) The overall attack rate as a function of the treatment level and the switch time for the start of zanamivir as the primary drug. The solid (black) line corresponds to 52% of the treatment level (fc=0.52) that minimizes the overall attack rate when oseltamivir is the only drug used for treatment of symptomatic infections