Swine influenza A virus subtype H3N2 (SIV H3N2)

Swine influenza virus H3N2 is a subtype of Influenza A virus that primarily circulates in swine populations but possesses significant zoonotic potential, occasionally infecting humans as variant viruses (H3N2v) [1][2]. The virus is an enveloped, negative-sense, single-stranded RNA virus belonging to the Orthomyxoviridae family [3]. Its genome encodes several key proteins that serve as therapeutic targets, most notably Hemagglutinin (H3) for attachment to host sialic acid receptors and Neuraminidase (N2) for the release of progeny virions [3][4]. In humans, H3N2v typically causes respiratory illness similar to seasonal flu, often linked to exposure at agricultural settings [1][5]. Pharmacological management focuses on inhibiting viral replication through drugs like oseltamivir, which targets the neuraminidase enzyme, or baloxavir marboxil, which targets the viral polymerase complex [4][6]. A major challenge in treating H3N2 is the high prevalence of resistance to M2 ion channel blockers like amantadine, alongside the constant threat of antigenic drift which can render vaccines and existing therapies less effective [5][6].

Other names

Swine-origin influenza A (H3N2) virusH3N2vSwine flu H3N2Influenza A virus (A/swine/H3N2)Variant influenza A (H3N2) virus

Neuraminidase inhibition (prevents release of viral progeny); Cap-dependent endonuclease inhibition (blocks viral mRNA synthesis); M2 ion channel blockade (inhibits viral uncoating)