Thus, a vaccine designed for a common ancestor could have a better chance of being effective for a larger proportion of circulating strains. Another team took this idea further by developing a center-of-tree reconstruction method to produce a sequence whose total evolutionary distance to contemporary strains is as small as possible.
The goal is to develop a vaccine that is more effective against a broader spectrum of circulating strains. A new approach involves creating a sequence that is as close as possible to the ancestral form, minimizing evolutionary distance from modern strains.