Infection of chick embryo tracheal organ cultures with influenza A2 (Hong Kong) virus.

Chick embryo tracheal organ culture was found to be a suitable system for the propagation of Influenza A 2 (Hong Kong) virus. Growth of the virus could be detected by the appearance of hemadsorption and immunofluorescence as early as 12 hours after infection. Cytopathic changes appeared before the cessation of ciliary activity. All of the above mentioned changes were found to be reliable indicators of viral growth and did not occur if influenza A 2 (Hong Kong) virus was mixed with specific antiserum and inoculation was made with this complex.