The rapid rise in various parts of the world of deadly, more infectious COVID-19 variants that share new mutations is leading scientists to ask a critical question — has the SARS-CoV-2 virus shown its best cards?

New variants first detected in such far-flung countries as Brazil, South Africa and the U.K. cropped up spontaneously, within a few months, late last year. All three share some of the same mutations in the important spike region of the virus used to enter and infect cells.

These include the E484k mutation, nicknamed "Eek" by some scientists for its apparent ability to evade natural immunity from previous COVID-19 infection and to reduce the protection offered by current vaccines — all of which target the spike protein.