Division 2 Detection of antibodies in unvaccinated birds

The majority of laboratories involved in Newcastle disease diagnosis are familiar with the haemagglutination inhibition test and the recommendation described below relate to this test for the measurement of antibodies to the virus. However, enzyme-linked immunosorbent assays (Elisa) may be successfully used to detect antibodies to the virus. It is suggested that if there is a wish to employ an Elisa test at regional laboratory level the test should be monitored by the national laboratory referred to in Annex II.