influenza a (h1n1) vaccine (surface antigen, inactivated)

The a/h1n1 subunit influenza vaccine is a monovalent, inactivated vaccine designed to provide active immunization against the Influenza A virus subtype H1N1, specifically the strain responsible for the 2009 pandemic (A/California/07/2009-like). As a subunit (or surface antigen) vaccine, it contains purified viral proteins—primarily hemagglutinin (HA) and neuraminidase (NA)—rather than the whole or split virus. These antigens are typically extracted from virus particles grown in embryonated chicken eggs or cell cultures through a process of chemical disruption and purification. Upon administration, the vaccine stimulates the immune system to produce neutralizing antibodies against the HA protein, which prevents the virus from attaching to and entering host respiratory cells. Subunit vaccines are generally associated with a lower reactogenicity profile compared to whole-virus or split-virion vaccines. A prominent example of this type is Novartis's Focetria, which was often formulated with the MF59 adjuvant to enhance the immune response in the context of pandemic preparedness.

Brand names

Focetria

Other names

a/h1n1 subunit influenza vaccinemonovalent h1n1 subunit vaccineh1n1 surface antigen vaccineh-1n1 surface antigen vaccineh 1n1 surface antigen vaccineinactivated h1n1 subunit influenza vaccine