The mainstay of efforts to lessen the significant health burden caused by seasonal influenza is influenza vaccination. Since the 1940s, there have been inactivated influenza vaccines available for intramuscular injection. Anyone aged six months or older can receive inactivated vaccines. The live attenuated, cold-adapted influenza vaccine (LAIV), which is given as a nasal spray, was created in the 1960s but was not approved for use in the US until 2003. Both vaccinations are trivalent preparations produced in egg-grown eggs and are adjuvant-free. The Seasonal Influenza Vaccines induces antibodies primarily against the major surface glycoproteins hemagglutinin (HA) and neuraminidase (NA); antibodies directed against the HA are most crucial for protection. In the United States, LAIV is approved for use in healthy non-pregnant individuals 2-49 years of age.
