Influenza B virus hemagglutinin and neuraminidase (HA and NA (when referring to individual proteins))

The primary surface antigens of Influenza B virus are the envelope glycoproteins hemagglutinin (HA) and neuraminidase (NA), which are embedded in the viral lipid envelope[2][4][5]. Hemagglutinin mediates virus attachment to host cell sialic acid receptors and catalyzes fusion of the viral and cellular membranes during entry[1][4]. Neuraminidase removes sialic acid residues from glycoproteins, facilitating release of new virions from infected cells and preventing viral self-aggregation[5]. Both proteins are the main targets of host neutralizing antibodies and are subject to immune-driven antigenic variation[1][5]. These structures serve as the basis for subtype nomenclature and as targets for licensed antivirals and vaccines for influenza B.

Other names

Influenza B virus surface glycoproteinsInfluenza B HAInfluenza B NAB/HA and B/NA

Inhibition of neuraminidase enzymatic activity blocks viral particle release from infected cells and limits spread[5]. Monoclonal antibodies prevent hemagglutinin-mediated cell entry and membrane fusion[1].