− | The '''immediate efficacy of vaccines''' suggests that they may be indicated for use during developing outbreaks.<ref>Sandhu, T. S., Leibovitz, L (1997) '''Duck virus enteritis (Duck Plague)'''. Calnek, B. W., Barnes, H. J., Beard, C. W., McDougald, L. R., Saif, Y. M. eds. Diseases of Poultry, ed 10. ''Ames, USA: Iowa State University Press'', 675-683.</ref> | + | The '''immediate efficacy of vaccines''' suggests that they may be indicated for use during developing outbreaks.<ref>Sandhu, T. S., Leibovitz, L (1997) '''Duck virus enteritis (Duck Plague)'''. Calnek, B. W., Barnes, H. J., Beard, C. W., McDougald, L. R., Saif, Y. M. eds. Diseases of Poultry, ed 10. ''Ames, USA: Iowa State University Press'', 675-683.</ref> This rapidity of action is thought to be due to the action of stimulated interferons, known as the "interference phenomenon". |