What makes a virus being successful is its ability to spread. Within or between hosts, when the viral genome spreads it can be considered a reproductive success. Using phylogenetics and phylodynamics we analyse the transmission routes of a virus to find ways to mitigate epidemics.
We can use the molecular sequences of the viral genomes to categorise them into different types. Viral types are either connected with different viral properties (e.g. virulence) or epidemic history, and molecular typing studies provide important information even for deeper, more basic problems such as the replication mechanism of the virus.