A Quantitative, Single-Radial-Diffusion Test for Immunological Studies with Influenza Virus Schild, G. C. and Henry-Aymard, Michele and Pereira, H. G.,, 16, 231-236 (1972), doi = https://doi.org/10.1099/0022-1317-16-2-231, publicationName = Microbiology Society, issn = 0022-1317, abstract= Antibodies for influenza haemagglutinin and neuraminidase are assayed routinely in haemagglutination-inhibition (Hirst, 1942) and neuraminidase-inhibition (Ada, Lind & Laver, 1963) tests which involve reaction systems of three components. More recently, influenza antibodies have been detected by gel immuno-double-diffusion tests with influenza viruses disrupted by detergents (Styk & Hanna, 1966; Schild & Pereira, 1969). Although the latter method has the advantage that it detects antibodies for each of the major antigens of the virus in a single test system (Schild et al. 1972a; Schild, 1972) the quantitation of antibody is not readily achieved. In the present report we describe a quantitative, single-radial-diffusion test which is a sensitive, rapid and convenient method for the estimation of antibodies to the haemagglutinin and neuraminidase antigens of the influenza virus. A unique feature of this test is that only one component, the antibody, diffuses during the test; the other component, the antigen in the form of intact influenza virus particles, does not diffuse., language=, type=