On Mar. 20, 2023, some of the world’s leading makers of flu vaccines said they could make hundreds of millions of bird flu shots for humans within months if a new strain of avian influenza ever jumps across the species divide.

Executives at three vaccine manufacturers – GSK Moderna and CSL Seqirus, told Reuters they were already developing or about to test sample human vaccines that better match the circulating subtype, as a precautionary measure against a future pandemic.