12.3 Incomplete sampling
The tree we just saw is the complete, “full” tree of transmission, but we are almost never able to sample all the individuals we need to reconstruct it.
Incomplete sampling can result in inaccurate interpretations of a phylogenetic tree (ex: inferring fewer introductions of the virus from a source population into a new population).
Fig. 2. Incomplete sampling complicates interpretations of a phylogeny (source).