The global sequencing effort makes this reasonably straightforward to study. While the prevalance of different strains does vary geographically, new internation

The global sequencing effort makes this reasonably straightforward to study. While the prevalance of different strains does vary geographically, new international tranmission events occur so frequently that most places have a handful of circulating strains already [0] [0] https://nextstrain.org/ncov/europe https://nextstrain.org/ncov/europe