Immunity against equine influenza virus infection.

摘要

Influenza virus plays an important role in respiratory diseases in horses. Equine influenza virus is represented by two different serotypes: H7N7 and H3N8. The strain H7N7 has not been isolated since 1980 and H3N8 circulates in the equine population throughout most of the world. For preventive and prophylactic measures inactivated and subunit vaccines are most commonly used. Contrary to natural infections, traditional vaccines induce neither cytotoxic lymphocytes T nor mucosal antibodies and they do not provide enduring immunity. There is also the difference in the immune response as the natural infection induces IgA, IgGa and IgGb antibodies whereas the traditional vaccines induce IgGc and IgG(T) and no IgA. The low efficacy of the traditional vaccines also depends on an antigenic drift of the surface glycoprotein-hemagglutynin.