Failure of vaccines to protect salmon from vibriosis enzootic in Puget Sound, Washington.

Juvenile chinook salmon in fresh water were vaccinated either orally or parenterally with heat- or formalin-killed bacterins prepared with Vibrio anguillarum. Subsequent exposure to naturally occuring vibriosis in the marine waters of Puget Sound (Washington State) indicated that no protection resulted. It was demonstrated, however, that protection could be achieved with the passive transfer of immune serum.