Fig. 6.
H5N1 virus replication in the organs of ducks that were vaccinated with recombinant DEV vaccines. Groups of three ducks were inoculated intramuscularly with 105 PFU (A, B, and C) or 106 PFU (D) of the recombinant DEVs or wild-type DEV or with PBS as a control. They then were challenged with the lethal H5N1 virus HB/49 intranasally at 3 days (A and D), 1 week (B), or 3 weeks (C) postvaccination. Three days after challenge, the ducks were euthanized and their organs were harvested for virus titration in eggs. The dashed lines show the limits of detection.