FILE – In this Friday, Dec. 11, 2020, file photo, a Pfizer Global Supply Kalamazoo manufacturing plant sign is shown in Portage, Mich. New research suggests that Pfizer’s COVID-19 vaccine can protect against a mutation found in two contagious variants of the coronavirus that erupted in Britain and South Africa.
Those variants are causing global concern. They both share a common mutation called N501Y, a slight alteration on one spot of the spike protein that coats the virus and is believed to be the reason they can spread so easily. (AP Photo/Paul Sancya, File)