Occurrence of influenza specific antibodies in the lung after oral immunization in mice

After nasal, oral and rectal immunization of Balb/c and CF 1 mice with influenza virus (A/PR/8/34, HON 1) specific antibodies (hemagglutination inhibition test) occur in serum and in the lung of mice, detectable in lung lavage fluids. The nasal route of immunization leads to slightly better local antibody production, but the oral route is a promising route, and should be tried in humans.