Viral co-infection does not reduce tbe efficacy of vaccination against non-typeable Haemophilus influenzae middle ear infection in a rat model

The mucosal vaccination of rodents with killed non-typeable Haemophilus inf luenzae (NTHi) has been previously shown to enhance live NTHi clearance fol lowing middle ear challenge. This study assessed the efficacy of mucosal an ti-NTHi vaccination during a concomitant viral infection of the respiratory tract. Animals were mucosally immunised with killed NTHi by intra-Peyer's patch primary inoculation and lung (intratracheal) boost. At the time of bo th immunisations rats were also infected intra-nasally with Sendai virus. C oncomitant Sendai virus infection did not influence the efficacy of anti-NT Hi vaccination mediated clearance of NTHi from the middle ear. This would s uggest that immunisation strategies to prevent bacterial middle ear infecti on would be effective despite the presence of concomitant viral agents. Cop yright (C) 2001 S. Karger AG, Basel.