influenza A (H1N1) 2009 monovalent subunit vaccine

The influenza A (H1N1) 2009 monovalent subunit vaccine is a viral vaccine developed to provide protection against the pandemic H1N1 influenza strain (swine flu) that emerged in 2009. Unlike split-virion or whole-virus vaccines, subunit vaccines (also known as surface antigen vaccines) contain only purified viral surface proteins, specifically hemagglutinin and neuraminidase, which have been isolated from the virus. This specific formulation was prominently developed by companies such as Novartis (under the brand Focetria) and CSL (under the brand Panvax). It was frequently administered with an adjuvant, such as MF59 (a squalene-based oil-in-water emulsion), to enhance immunogenicity and facilitate antigen-sparing, allowing for a broader reach during a pandemic. The vaccine functions by stimulating the host immune system to generate neutralizing antibodies that target the viral hemagglutinin, thereby preventing the virus from attaching to and infecting host respiratory cells.

Brand names

FocetriaPanvaxCeltura

Other names

A/H1N1 2009 monovalent subunit vaccine2009 H1N1 monovalent vaccineH1N1 2009 monovalent subunit vaccineH-1N1 2009 monovalent subunit vaccineH 1N1 2009 monovalent subunit vaccineSwine flu vaccine