RNA virus Speed fidelity trade-off

The paradigm in virus evolution is that high viral mutation rates are advantageous, because they lead to increased genetic diversity, which allows for rapid adaptation and enhanced virulence. In this study we tested an alternative model whereby RNA viruses evolved high mutation rates as a byproduct of selection for replicative speed. In contrast to quasispecies models, we find that virulence is associated with viral replicative speed and not standing genetic diversity.