Immunogenicity of egg-grown influenza vaccine: inhibition by immunization of recipients with host antigen.

Rabbit antibody directed against normal allantoic fluid reduced the protective power of influenza vaccine prepared from egg-grown PR8 virus. A similar vaccine prepared from mouse lung virus was not inhibited. Preimmunization of mice with normal allantoic fluid or with egg-grown influenza B/Lee vaccine (crude or purified) inhibited the protective power of PR8 egg vaccine but did not affect a similar lung vaccine.