The BA.2.86 spike protein has the potential to bypass the immune system because of its unusually high number of mutations — A new Covid-19 variant, BA.2.86, dubbed Pirola, has 34 mutations to its spike protein relative to BA.2 (its ancestor), as well as 36 mutations relative to XBB.1.5 (the dominant strain earlier this year), according to Dr. Jesse Bloom, of the Fred Hutchinson Cancer Center in Seattle.