Figure 4
From: Clinically immune hosts as a refuge for drug-sensitive malaria parasites
Effective reproductive rate and fitness cost of resistance. The higher the fitness cost of resistance (1 - r w /r x ), the lower the absolute level of the effective reproductive number. Qualitatively, this suggests an important implication: it is always more difficult for the parasite to evolve (i.e., emerge and spread) resistance in higher-transmission settings.