Indirect hemagglutination with duck hepatitis virus.

The virus-neutralization (VN) and the agar-gel diffusion procedures are the only tests that have been developed for the demonstration of duck hepatitis virus (DHV) antibodies (11). The VN test has been the basic serologic procedure for the study of virus infections, and its high degree of immunologic specificity makes it the standard by which other serologic methods are usually evaluated. However, VN tests require considerable time, materials, and equipment, which limits their value. Since DHV has not been shown to agglutinate avian or mammalian erythrocytes, an indirect hemagglutination (IHA) test was developed for the demonstration of DHV antibodies.