Abstract
BACKGROUND: Haemophilus influenzae requires heme for aerobic growth and possesses multiple mechanisms to obtain this essential nutrient. METHODS: An insertional mutation in tonB was constructed and the impact of the mutation on virulence and fitness in a chinchilla model of otitis media was determined. The tonB insertion mutant strain was significantly impacted in both virulence and fitness as compared to the wildtype strain in this model. CONCLUSIONS: The tonB gene of H. influenzae is required for the establishment and maintenance of middle ear infection in this chinchilla model of bacterial disease.