Detection of type A influenza virus among 30 cases of duck samples

  Objective   To study the carrying rate of type A influenza among health ducks recently in one of Shanghai poultry sacrifice ground.

  Methods   The cotton swab samples from mouth and anal of ducks were mixed to be cultured in egg embryo and to the potential influenza virus was amplified by using chicken blood agg lutination.Then PCR amplification of conserved type A influenza virus NP protein nucleotide sequene was used to determinate type A virus infection.

  Results   50% of 30 samples were positive in 1:50 blood agglutination test, 9 of 10 samples amplified correctly by PCR were with type A influenza virus.

  Conclusion   Approximate 45% of normal ducks could be detected with type A influenza virus by using the method.