Models of RNA virus evolution and their roles in vaccine design

Ojosnegros, Samuel; Beerenwinkel, Niko

Live attenuated vaccines (LAVs). Immunization with LAV has been proved to be the most efficient vaccination strategy to date [34, 35] . LAV preparations include viruses with reduced virulence, which means that they do not produce the disease when infecting the host, or they produce a mild version of the disease. Viruses become attenuated for the original host after serial infections (passages) in cell culture of different organism. This is the case of the polio vaccine preparation in monkey cells [36] . Infection of embryonated hen eggs is the standard protocol to obtain attenuated yellow fever or measles viruses suitable for vaccine preparation [37] . The rationale for this attenuation strategy is that due to the high error rates during replication of viruses, especially of RNA viruses [2] , the virus accumulates mutations in the genome that optimize their replication in the new host or new cell type, at the expense of replication efficiency in the original host [1, 34, 38] .