Antibodies, and antigen binding fragments thereof, that specifically bind to an epitope in the stem region of an influenza A hemagglutinin trimer and neutralize a group 1 subtype and a group 2 subtype of influenza A virus. Nucleic acids that encode, immortalized B cells and cultured single plasma cells that produce, and to epitopes that bind to such antibodies and antibody fragments. In addition, the use of the antibodies, antibody fragments, and epitopes in screening methods as well as in the diagnosis, treatment and prevention of influenza A virus infection.
