Abstract
A quantitative hemadsorption-inhibition test was developed to estimate myxovirus serum antibodies within 24 h by determining the serum dilution inhibiting hemadsorption in 50% of the infected cells. The test depends on the interactions of virus-infected cell monolayers with antiviral serum and of the resultant complexes with antiimmunoglobulin G serum. The incorporation of species-specific anti-immunoglobulin G serum into the test significantly increased sensitivity.