Temporal variations of country-specific mutational profile of SARS-CoV-2: effect on vaccine efficacy.

In order to curb the transmission of SARS-CoV-2, nation-wide travel restrictions at different levels were implemented in different countries. Country-specific mutational profile may exist and have an impact on vaccine efficacy. We identified nonsynonymous mutations in approximately 215,000 SARS-CoV-2 sequences during the 1st year of the pandemic in 35 countries. Mutational profiles on a bimonthly basis were traced over time. We also examined the mutations that overlapped with the spike protein vaccine epitopes. Several new mutations emerged over time and were dominating in specific countries. Many nonsynonymous mutations were within multiple spike protein epitopes that might impact the vaccine efficacy. Our study advocates requirement of active monitoring of country-specific mutations and vaccine efficacies in respective countries.