On Jun. 14, 2024 the Centers for Disease Control and Prevention reported data from this study suggested that there is extremely low to no population immunity to clade 2.3.4.4b A(H5N1) viruses in the United States.

Antibody levels remained low regardless of whether or not the participants had gotten a seasonal flu vaccination, meaning that seasonal flu vaccination did not produce antibodies to A(H5N1) viruses.